Saltwater Questions - Beginner Here

LifeOfAquatics · Mar 17, 2021

Hello, I am thinking of starting a 20-gallon long reef tank soon and I wanted to ask some questions in hopes of getting answers. If you could, please label your answers with numbers so that I know which question you are responding to. Thanks in advance!

All this is for a 20 Gallon Long Reef Tank with RODI water

1. Can you house two different types of clownfish together? (i.e. black ocellaris and regular ocellaris clown (which is what I want to do personally))
2. Would you recommend anemones/zoanthids in a beginner reef tank? Do clownfish even need them?
3. What are some corals you would suggest to a beginner starting a reef tank in a 20 gallon long?
4. Best fish/stocking ideas for a 20 gallon long?
5. Would buying live rock from Petco (not from the tank, but the individually prepackaged ones) and mixing it with dry rock work in curing the rocks? If I buy live pre packaged rock from Petco, I don’t have to cure it right? I can just throw it in there?
6. I feel like this is a dumb question, would you suggest buying live rock and/or corals from Petco? What about fish? Ik dumb question but im curious lol
7. What are some good lights for corals that are budget-friendly?
8. Do I need to quarantine or dip corals or anything like that? How would I go about doing this?
9. Do you need to feed corals? I heard that most of the time not right? If I do, what should I go abt feeding them?
10. Should I get a protein skimmer for a 20 gallon long? Or is a HOB filter enough?
11. Is there a limit to CUC? Obvi I won’t overdo it like 30 emerald crabs or anything lol but like do you have any CUC stocking suggestions for me?
12. So I really like tangs, I just like the idea of feeding one and how they look, do you have any suggestions for fish that are sort of like tangs in that they are semi large, peaceful for the most part, reef safe, like seaweed (I just really like the thought of hand feeding a tang lol), and is good for a 20 gallon? Im totally cool if there isn’t, just it would be nice to have like a centerpiece fish. What abt a 29 gallon?
13. After some research, I have decided that I am TERRIFIED of bristle worms, just the way they look, the fact that they can harm you, they can kill your fish, there are a parasite, just ugh. Are there any reef safe peaceful fish/inverts for a 20 long which will kill bristle worms? Is there any way to check to see if rocks have them? Any traps or ways to get rid of them?
14. Can you house only one clownfish but other fish like gobies, Firefish, etc. just not have a pair of them, just one but with other species of fish?
15. Would 2 clownfish, 2 Cardinalfish, 1 Firefish, and 1 watchman goby along with some CUC work in a 20 long? I definitely plan to have live rock and sand and if need be, I will get a filter which is a size bigger than my tank (I.e. a 40 gallon filter for a 20 gallon tank). Would this work? If it wouldn’t work, could you tell me why and other stocking alternatives?
16. If I buy live rock from say my LFS, do I need to quarantine it or cure it? Also, if I have some live and some dry rock, can I just put that both into my tank and let the dry rock cure in there for about a month with say Dr. Tim’s One and Only (I think thats what it is called)?
17. So in my research, I found that a 20 gallon tank will lose roughly 1.75 gallons a week or .26 gallons a day. Is it OK if I top off my tank every two days manually? I am asking because I generally feed all my pets once every two days, so I could top off whilst feeding. Would this work or would it mess up the stability of my tank? Also I plan on having a tight lid like a glass lid. If I do put a glass lid, how much can I expect my average top off gallonage to go down by? As in, compared to without a lid/screen lid, can anyone estimate what the difference will be if I use a glass lid?
18. Can saltwater fish be fed once every two days?
19. Is it possible to top off every week or something like every 4 days or would it mess up my stability?
20. How often should I clean my reef tank? I normally clean all my tanks every 2-3 weeks, 3 weeks sometimes for a planted tank, 2 weeks for axolotl, but I if I am being honest rarely do once a week. I have a python system so doing it weekly is not too big of a problem, I just don’t really choose to lol and all my pest have been fine

CMMorgan · Mar 17, 2021

LifeOfAquatics said:
Hello, I am thinking of starting a 20-gallon long reef tank soon and I wanted to ask some questions in hopes of getting answers. If you could, please label your answers with numbers so that I know which question you are responding to. Thanks in ad

All this is for a 20 Gallon Long Reef Tank with RODI water

1. Can you house two different types of clownfish together? (i.e. black ocellaris and regular ocellaris clown (which is what I want to do personally)) Yes, I have three different types in mine.
2. Would you recommend anemones/zoanthids in a beginner reef tank? Only once well established and stable. Do clownfish even need them? No. My clown has adopted my waving hand xenia as it's home.
3. What are some corals you would suggest to a beginner starting a reef tank in a 20 gallon long? Softies - shrooms, Kenya tree, zoas, GSP... but get the tank stable first
4. Best fish/stocking ideas for a 20 gallon long? Any nano fish. You don't have a lot of real estate so make it count.
5. Would buying live rock from Petco (not from the tank, but the individually prepackaged ones) and mixing it with dry rock work in curing the rocks? If I buy live pre packaged rock from Petco, I don’t have to cure it right? I can just throw it in there? Do not buy anything that has lived inside a Petco display tank.... not worth it. Find a LFS.
6. I feel like this is a dumb question, would you suggest buying live rock and/or corals from Petco? What about fish? Ik dumb question but im curious lol See question 5
7. What are some good lights for corals that are budget-friendly? There are several black box options out there. For a tank that size, if you ever want to get into SPS, you can get by with one Kessil 360. It will cost more but you only need one.
8. Do I need to quarantine or dip corals or anything like that? How would I go about doing this? Yes and yes. Just search the thread about the spiders ... and aiptasia... you will want to dip and OT. It's pretty basic - Coral Rx, 4 capfuls to a gallon for 10 minutes then rinse in clean salt water and place into the QT.
9. Do you need to feed corals? I heard that most of the time not right? If I do, what should I go abt feeding them? Some do like to be fed. Many use Reef Roids. Corals like torches like mysis or maybe pellets. Many corals are photosynthetic - meaning they get energy from light. Before adding any coral to the tank, do a search to learn it's lighting, flow and food requirements.
10. Should I get a protein skimmer for a 20 gallon long? Or is a HOB filter enough? They make many small protein skimmers. Just stay away from Seaclone.
11. Is there a limit to CUC? Obvi I won’t overdo it like 30 emerald crabs or anything lol but like do you have any CUC stocking suggestions for me? Trochus, Nassarius, Nerite Snails, Some hermit crabs.... check out reefkeepers.com. They can guide you based on the type of tank you have. Great people - very wise.
12. So I really like tangs, I just like the idea of feeding one and how they look, do you have any suggestions for fish that are sort of like tangs in that they are semi large, peaceful for the most part, reef safe, like seaweed (I just really like the thought of hand feeding a tang lol), and is good for a 20 gallon? Im totally cool if there isn’t, just it would be nice to have like a centerpiece fish. What abt a 29 gallon? None. That is cruel. Please do not do that to the poor fish.
13. After some research, I have decided that I am TERRIFIED of bristle worms, just the way they look, the fact that they can harm you, they can kill your fish, there are a parasite, just ugh. Are there any reef safe peaceful fish/inverts for a 20 long which will kill bristle worms? Is there any way to check to see if rocks have them? Any traps or ways to get rid of them? Unless you are getting live rock from Gluf Live Rock, KT Aquatics, TBS, etc... your chances of having bristle worms are low. Not saying impossible... but they do not come in bagged sand at Petco. That said... I always suggest wearing gloves.
14. Can you house only one clownfish but other fish like gobies, Firefish, etc. just not have a pair of them, just one but with other species of fish? If you have a firefish, get a lid.... they spook easy and they jump.
15. Would 2 clownfish, 2 Cardinalfish, 1 Firefish, and 1 watchman goby along with some CUC work in a 20 long? I definitely plan to have live rock and sand and if need be, I will get a filter which is a size bigger than my tank (I.e. a 40 gallon filter for a 20 gallon tank). Would this work? If it wouldn’t work, could you tell me why and other stocking alternatives? If you are going to use a HOB, get one that is way bigger than it is rated. Those are notoriously underrated on the boxes.
16. If I buy live rock from say my LFS, do I need to quarantine it or cure it? Also, if I have some live and some dry rock, can I just put that both into my tank and let the dry rock cure in there for about a month with say Dr. Tim’s One and Only (I think thats what it is called)? If there is nothing else in the tank, then yes... go ahead and put all of the rock and sand in with some Dr. Tim's. Let the tank cycle and then add life. Keep in mind that your LFS "live rock" was just dry rock that they put in a wet in for a while. It is seeded with live bacteria but not the same as "live rock" that you get from Tampa Bay Saltwater - which sits in the ocean for years before they sell it to you.
17. So in my research, I found that a 20 gallon tank will lose roughly 1.75 gallons a week or .26 gallons a day. Is it OK if I top off my tank every two days manually? I am asking because I generally feed all my pets once every two days, so I could top off whilst feeding. Would this work or would it mess up the stability of my tank? Also I plan on having a tight lid like a glass lid. If I do put a glass lid, how much can I expect my average top off gallonage to go down by? As in, compared to without a lid/screen lid, can anyone estimate what the difference will be if I use a glass lid? When you can afford it, get an ATO. It will give you the most stability. Things like salinity and PH can swing fast in a nano tank. You can top off the ATO reservoir every two days. Regarding the glass lid... it will also collect salt creep. That ad condensation will inhibit the light and reduce PAR - i.e. the effectiveness of the light. It also creates a greenhouse effect - raising temp. If you want a liud for the firefish - use one made our of screen.
18. Can saltwater fish be fed once every two days? No
19. Is it possible to top off every week or something like every 4 days or would it mess up my stability? No
20. How often should I clean my reef tank? I normally clean all my tanks every 2-3 weeks, 3 weeks sometimes for a planted tank, 2 weeks for axolotl, but I if I am being honest rarely do once a week. I have a python system so doing it weekly is not too big of a problem, I just don’t really choose to lol and all my pest have been fine. Like your other tanks... as needed. Keep an eye on the Corraline algae though. It sneaks up on you. If it starts blocking your view, use an old credit card to clean it off.

I hope that gets you started. Welcome to the fishy family!!! Please post pics of the axolotl! They have always fascinated me. There used to be a good LFS in Gwinnett County - I think it was near Steve Reynolds Blvd when I lived there. Perhaps they can help you out.

Jekyl · Mar 17, 2021

Welcome to R2R! Give me an hour to read through your list and I'll try to answer them all (just kidding)

Azedenkae · Mar 17, 2021

LifeOfAquatics said:
Hello, I am thinking of starting a 20-gallon long reef tank soon and I wanted to ask some questions in hopes of getting answers. If you could, please label your answers with numbers so that I know which question you are responding to. Thanks in advance!

All this is for a 20 Gallon Long Reef Tank with RODI water

1. Can you house two different types of clownfish together? (i.e. black ocellaris and regular ocellaris clown (which is what I want to do personally))
2. Would you recommend anemones/zoanthids in a beginner reef tank? Do clownfish even need them?
3. What are some corals you would suggest to a beginner starting a reef tank in a 20 gallon long?
4. Best fish/stocking ideas for a 20 gallon long?
5. Would buying live rock from Petco (not from the tank, but the individually prepackaged ones) and mixing it with dry rock work in curing the rocks? If I buy live pre packaged rock from Petco, I don’t have to cure it right? I can just throw it in there?
6. I feel like this is a dumb question, would you suggest buying live rock and/or corals from Petco? What about fish? Ik dumb question but im curious lol
7. What are some good lights for corals that are budget-friendly?
8. Do I need to quarantine or dip corals or anything like that? How would I go about doing this?
9. Do you need to feed corals? I heard that most of the time not right? If I do, what should I go abt feeding them?
10. Should I get a protein skimmer for a 20 gallon long? Or is a HOB filter enough?
11. Is there a limit to CUC? Obvi I won’t overdo it like 30 emerald crabs or anything lol but like do you have any CUC stocking suggestions for me?
12. So I really like tangs, I just like the idea of feeding one and how they look, do you have any suggestions for fish that are sort of like tangs in that they are semi large, peaceful for the most part, reef safe, like seaweed (I just really like the thought of hand feeding a tang lol), and is good for a 20 gallon? Im totally cool if there isn’t, just it would be nice to have like a centerpiece fish. What abt a 29 gallon?
13. After some research, I have decided that I am TERRIFIED of bristle worms, just the way they look, the fact that they can harm you, they can kill your fish, there are a parasite, just ugh. Are there any reef safe peaceful fish/inverts for a 20 long which will kill bristle worms? Is there any way to check to see if rocks have them? Any traps or ways to get rid of them?
14. Can you house only one clownfish but other fish like gobies, Firefish, etc. just not have a pair of them, just one but with other species of fish?
15. Would 2 clownfish, 2 Cardinalfish, 1 Firefish, and 1 watchman goby along with some CUC work in a 20 long? I definitely plan to have live rock and sand and if need be, I will get a filter which is a size bigger than my tank (I.e. a 40 gallon filter for a 20 gallon tank). Would this work? If it wouldn’t work, could you tell me why and other stocking alternatives?
16. If I buy live rock from say my LFS, do I need to quarantine it or cure it? Also, if I have some live and some dry rock, can I just put that both into my tank and let the dry rock cure in there for about a month with say Dr. Tim’s One and Only (I think thats what it is called)?
17. So in my research, I found that a 20 gallon tank will lose roughly 1.75 gallons a week or .26 gallons a day. Is it OK if I top off my tank every two days manually? I am asking because I generally feed all my pets once every two days, so I could top off whilst feeding. Would this work or would it mess up the stability of my tank? Also I plan on having a tight lid like a glass lid. If I do put a glass lid, how much can I expect my average top off gallonage to go down by? As in, compared to without a lid/screen lid, can anyone estimate what the difference will be if I use a glass lid?
18. Can saltwater fish be fed once every two days?
19. Is it possible to top off every week or something like every 4 days or would it mess up my stability?
20. How often should I clean my reef tank? I normally clean all my tanks every 2-3 weeks, 3 weeks sometimes for a planted tank, 2 weeks for axolotl, but I if I am being honest rarely do once a week. I have a python system so doing it weekly is not too big of a problem, I just don’t really choose to lol and all my pest have been fine

1. Yes.
2. The general consensus seems to be anemones are not great for beginners, zoas can be okay though. Clownfish don't really need anemones.
3. Personally I like glove polyps, but they can become a 'pest'. I don't mind though, I actually want them to spread everywhere.
4. Since you are probably set on the two clownfish, probably just other small fish, maybe. The thing is clownfish can get pretty big and also pretty aggressive, so they can take over a 20 gallon tank. Maybe not right away, but eventually.
5. I don't know what 'curing' is defined as anymore, so I'll reserve this to someone else.
6. I have heard bad things about Petco, but also some good things for some specific ones sometimes, and I have never shopped or even been to one, so probably best I do not offer a clear opinion on this at the moment.
7. What is your budget? I don't think I can help with a suggestion, but a specific dollar amount would probably allow others to effectively suggest options.
8. I don't because I am lazy, but well, yeah probably a good thing to quarantine and stuff. I found aiptasia attached to one of mine, and seemed to have taken care of it. For now.
9. Depends on which coral species. I keep mostly softies, so these are kinda easier to handle.
10. A HOB filter is enough. Depends on what sort of filtration system as a whole you rely on though.
11. Probably an emerald crab or two, like maybe 15 nassarius snails, and a few more small-ish cuc should work.
12. Off the top of my head, no.
13. I dunno the answer to this one.
14. Yes. One clown is fine.
15. Probably not in the long term, as in they would probably all get big enough to make it super crowded and stuff.
16. Again don't know how 'curing' is defined anymore, so I can't answer this question. Personally though, I would add whatever rock I want to the tank, and let it cycle. But that's just me.
17. Yes you can top up manually every two days. If you keep some of the more sensitive live stock, it is probably good to do it slowly. I don't, so I just dump freshwater into the last chamber of my filter steadily.
18. I am not sure, at least not for 'saltwater fish' broadly. I would imagine though it depends on specific species.
19. The more often the top off, generally the better it is.
20. I scrape my glass almost everyday, manually remove algae every few days, and otherwise do not do anything except water changes every month or so.

Jekyl · Mar 17, 2021

1: yes you can. Just make sure they are both small when introduced.

2: wait at least 9 months before you try an anemone.

3: wait about a month or more to add first corals. GSP, leathers, mushrooms, zoas

4: 2 clowns and maybe 1 or 2 small fish is all you should put in a 20. Make sure you wait some time between adding fish.

5&6 If you want live rock check out gulfliverock.com or kp aquatics out of Florida. Otherwise just get dry. No one trusts petco.

7: for budget that will do all corals check out viparspectra 165w

All right that's enough lol... check out all of the sticky posts on here. Quarantine is a personal and heated debate. You'll have to research and decide for yourself. Get yourself an RoDi system for your water. Get salifert test kits.

Azedenkae · Mar 17, 2021

Jekyl said:
All right that's enough lol... check out all of the sticky posts on here. Quarantine is a personal and heated debate. You'll have to research and decide for yourself. Get yourself an RoDi system for your water. Get salifert test kits.

Sorry, random question - I remember reading recently somewhere that Salifert test kits were highly unreliable, I think maybe in the bottled bacteria experimentation thread by Dr. Reef or something. Am I remembering this correctly? Has it always been the case, or just a bad batch perhaps? Or has it always been reliable? I tried to google it but... was hard to find anything concrete.

Jekyl · Mar 17, 2021

Azedenkae said:
Sorry, random question - I remember reading recently somewhere that Salifert test kits were highly unreliable, I think maybe in the bottled bacteria experimentation thread by Dr. Reef or something. Am I remembering this correctly? Has it always been the case, or just a bad batch perhaps? Or has it always been reliable? I tried to google it but... was hard to find anything concrete.

I have never heard any complaints about salifert. Usually API is the culprit. I have always used them and hadn't had an issue.

vetteguy53081 · Mar 17, 2021

LifeOfAquatics said:
Hello, I am thinking of starting a 20-gallon long reef tank soon and I wanted to ask some questions in hopes of getting answers. If you could, please label your answers with numbers so that I know which question you are responding to. Thanks in advance!

All this is for a 20 Gallon Long Reef Tank with RODI water

1. Can you house two different types of clownfish together? (i.e. black ocellaris and regular ocellaris clown (which is what I want to do personally)) YES
2. Would you recommend anemones/zoanthids in a beginner reef tank? Do clownfish even need them? Anemones and zoa after 4-6 weeks of good test readings and stable environment.
3. What are some corals you would suggest to a beginner starting a reef tank in a 20 gallon long? mushroom, zoa, leather such as toadstool, xenia, candy cane coral
4. Best fish/stocking ideas for a 20 gallon long?Firefish goby, twin spot blenny, Chromis trio, 6 line wrasse, strawberry basslet, flame angel
5. Would buying live rock from Petco (not from the tank, but the individually prepackaged ones) and mixing it with dry rock work in curing the rocks? If I buy live pre packaged rock from Petco, I don’t have to cure it right? I can just throw it in there? Buy live rock but NOT from Petco. (one day you'll know why)
6. I feel like this is a dumb question, would you suggest buying live rock and/or corals from Petco? What about fish? Ik dumb question but im curious lol NOTHING From Petco
7. What are some good lights for corals that are budget-friendly? Ai Prime, Orphek OR3 light bars, Vivarspectra LED
8. Do I need to quarantine or dip corals or anything like that? How would I go about doing this? Always dip for yours and tank's safety
9. Do you need to feed corals? I heard that most of the time not right? If I do, what should I go abt feeding them? 1-2X per week is ample and Powdered foods or mysis and rotifiers
10. Should I get a protein skimmer for a 20 gallon long? Or is a HOB filter enough? Skimmer beneficial (Ice Cap K2-50)
11. Is there a limit to CUC? Obvi I won’t overdo it like 30 emerald crabs or anything lol but like do you have any CUC stocking suggestions for me?(get 3 each- Turbo, asttrea, trochus, cerith and nerite snails
12. So I really like tangs, I just like the idea of feeding one and how they look, do you have any suggestions for fish that are sort of like tangs in that they are semi large, peaceful for the most part, reef safe, like seaweed (I just really like the thought of hand feeding a tang lol), and is good for a 20 gallon? Im totally cool if there isn’t, just it would be nice to have like a centerpiece fish. What abt a 29 gallon? Kole eye Tang
13. After some research, I have decided that I am TERRIFIED of bristle worms, just the way they look, the fact that they can harm you, they can kill your fish, there are a parasite, just ugh. Are there any reef safe peaceful fish/inverts for a 20 long which will kill bristle worms? Is there any way to check to see if rocks have them? Any traps or ways to get rid of them? Arrow crab
14. Can you house only one clownfish but other fish like gobies, Firefish, etc. just not have a pair of them, just one but with other species of fish? Yes - see list above
15. Would 2 clownfish, 2 Cardinalfish, 1 Firefish, and 1 watchman goby along with some CUC work in a 20 long? I definitely plan to have live rock and sand and if need be, I will get a filter which is a size bigger than my tank (I.e. a 40 gallon filter for a 20 gallon tank). Would this work? If it wouldn’t work, could you tell me why and other stocking alternatives? Yes- Stock slowly
16. If I buy live rock from say my LFS, do I need to quarantine it or cure it? Also, if I have some live and some dry rock, can I just put that both into my tank and let the dry rock cure in there for about a month with say Dr. Tim’s One and Only (I think thats what it is called)? Ask them if its been QT or observe where the rock is diplayed in the store
17. So in my research, I found that a 20 gallon tank will lose roughly 1.75 gallons a week or .26 gallons a day. Is it OK if I top off my tank every two days manually? I am asking because I generally feed all my pets once every two days, so I could top off whilst feeding. Would this work or would it mess up the stability of my tank? Also I plan on having a tight lid like a glass lid. If I do put a glass lid, how much can I expect my average top off gallonage to go down by? As in, compared to without a lid/screen lid, can anyone estimate what the difference will be if I use a glass lid? I use glass lids. I still lose water but slower. Add to water flow slowly and use RODI water
18. Can saltwater fish be fed once every two days? 1-2X per day would be best. Consider and auto feeder
19. Is it possible to top off every week or something like every 4 days or would it mess up my stability? Top off as needed. And FW only- not saltwater unless doing a water change
20. How often should I clean my reef tank? I normally clean all my tanks every 2-3 weeks, 3 weeks sometimes for a planted tank, 2 weeks for axolotl, but I if I am being honest rarely do once a week. I have a python system so doing it weekly is not too big of a problem, I just don’t really choose to lol and all my pest have been fine Your water tests will indicate when the need arises. Biweekly is fine

LifeOfAquatics · Mar 17, 2021

CMMorgan said:
I hope that gets you started. Welcome to the fishy family!!! Please post pics of the axolotl! They have always fascinated me. There used to be a good LFS in Gwinnett County - I think it was near Steve Reynolds Blvd when I lived there. Perhaps they can help you out.

Thanks! But I wanted to clarify a couple of things...

12. So I didn't mean that I wanted to keep a tang in a 20, just a tang like fish. Is there any fish that look like tangs such as a dwarf angel or something like that that you would recommend?

14. Would 1 clown work with cardinals, firefish, goby, etc. Just without other clowns?

15. Would the livestock choices I made work?

16. How long should I cycle a tank with live and dry rock with Dr. Tims?

17. But would topping off every 2 days be OK?

18. How often should saltwater fish be fed?

vetteguy53081 · Mar 17, 2021

Azedenkae said:
Sorry, random question - I remember reading recently somewhere that Salifert test kits were highly unreliable, I think maybe in the bottled bacteria experimentation thread by Dr. Reef or something. Am I remembering this correctly? Has it always been the case, or just a bad batch perhaps? Or has it always been reliable? I tried to google it but... was hard to find anything concrete.

Salifert good- API UNRELIABLE

Azedenkae · Mar 17, 2021

Jekyl said:
I have never heard any complaints about salifert. Usually API is the culprit. I have always used them and hadn't had an issue.

vetteguy53081 said:
Salifert good- API UNRELIABLE

Okay thanks, I suppose it might have just been an isolated incident or something.

vetteguy53081 · Mar 17, 2021

checklist for saltwater aquarium at home illustration

The items listed here are pieces of equipment and components that are fundamental for setting up and running a saltwater aquarium or reef system.

Aquarium/Tank
You need to decide where you want to put your aquarium, determine what size you want or may only have room for, whether you want an acrylic or glass tank, and choose a style that will best fit into the spot you have picked out to display it.
Lighting
The type of lighting you choose will be based on the type of system you have planned to set up, as well as what kind of livestock you will be keeping in it.
Skimmers, Filters & Filtration Equipment
Once again, what type of system you are going to set up will help you determine which kind of filters and filtration system to choose.
Powerhead
Depending on the size of your aquarium, the use of one or several powerheads is an excellent way to provide good water circulation throughout the system.
Live Rock & Substrate
Here you need to decide on what type of material you want on the bottom of the tank, as well as whether you want to start with a live or non-living medium. Live rock plays an important role in a marine tank. Many marine animals, fish in particular, can be quite territorial. It is important to provide ample shelter or places where the animals can hide, sleep, and avoid potential problems with aggression from other tankmates in the confined space of an aquarium.
Sea Salt Mix/Saltwater & Hydrometer
Sea salts are what make an aquarium a saltwater or marine aquarium. Also referred to as a salinity tester, this item measures the specific gravity or salt content of the water.
Heater & Thermometer
For smaller aquariums one heater works well, but for larger systems the use of multiple units is advised. With stick-on, floating, multi-function remote digital sensor, and many other types of units to pick from, the material a thermometer is made of is an important factor when choosing one as well.
Air Pump & Air Stones
Only needed if you are going to run a piece of equipment that requires these items, such as a counter-current protein skimmer.
Test Kits, Additives & Supplements
For live rock and reef tank systems, calcium (a.k.a. limewater/kalkwasser) needs to be added. Other supplemental vitamins or additives that are beneficial to the health of certain marine inhabitants you may be keeping, such a iodine for crustaceans, are important as well.
Maintenance Tools & Supplies
This category includes having items on hand such as a various sized plastic buckets or containers, tank cleaning tools such as a siphon tube/hose, an algae scraper or magnet, as well as nets of different sizes, spare equipment replacements parts, and so on. A good way to keep track of what maintenance tasks you have preformed and when is to keep a log book or record of everything you do.

Bfragale · Mar 17, 2021

Freshwater Molly’s are a great fish to concider. They can easily be acclimated to salt water are are a great clean up crew- not as good as a tang but maybe next best lol. Also a algae blenny will help as clean up crew too.

Jekyl · Mar 17, 2021

LifeOfAquatics said:
Thanks! But I wanted to clarify a couple of things...

12. So I didn't mean that I wanted to keep a tang in a 20, just a tang like fish. Is there any fish that look like tangs such as a dwarf angel or something like that that you would recommend?

14. Would 1 clown work with cardinals, firefish, goby, etc. Just without other clowns?

15. Would the livestock choices I made work?

16. How long should I cycle a tank with live and dry rock with Dr. Tims?

17. But would topping off every 2 days be OK?

18. How often should saltwater fish be fed?

For your stocking you don't need 2 clowns, one is fine. Check out liveaquaria.com they have minimum tank size for every fish you can think of. For cycling Dr tims will work. Just make sure to get some salifert test kits also. When your tank can go from 2ppm ammonia to zero in 24 hours you can do a large water change and add your first fish or 2. Give it some time after that

LifeOfAquatics · Mar 17, 2021

"4. Best fish/stocking ideas for a 20 gallon long? Firefish goby, twin spot blenny, Chromis trio, 6 line wrasse, strawberry basslet, flame angel"

I agree with everything but I am a little hesitant about the stocking. 8 fish seems like way too much for a 20G, and the 6 line, strawberry basslet, and flame angel are recommended for a 30G. Any thing else that is a little less bioload?

Bfragale · Mar 17, 2021

LifeOfAquatics said:
"4. Best fish/stocking ideas for a 20 gallon long? Firefish goby, twin spot blenny, Chromis trio, 6 line wrasse, strawberry basslet, flame angel"

I agree with everything but I am a little hesitant about the stocking. 8 fish seems like way too much for a 20G, and the 6 line, strawberry basslet, and flame angel are recommended for a 30G. Any thing else that is a little less bioload?

I would skip the cromis. 6 line should be ok- and great for picking flat worms or other potential pests but 20 is a bit small. But I’m a fan of six lines and algae blended in every tank lol.
Flame angel may be hard to get as this is a Hawaii fish that’s hard to get now I believe.

Jekyl · Mar 17, 2021

LifeOfAquatics said:
"4. Best fish/stocking ideas for a 20 gallon long? Firefish goby, twin spot blenny, Chromis trio, 6 line wrasse, strawberry basslet, flame angel"

I agree with everything but I am a little hesitant about the stocking. 8 fish seems like way too much for a 20G, and the 6 line, strawberry basslet, and flame angel are recommended for a 30G. Any thing else that is a little less bioload?

All of those fish are on liveaquaria.com just check the minimum tank recommendation for any of them. Depending on size of the fish 3 or 4 is going to be the max you should have in a 20 gallon.

CMMorgan · Mar 17, 2021

LifeOfAquatics said:
Thanks! But I wanted to clarify a couple of things...

12. So I didn't mean that I wanted to keep a tang in a 20, just a tang like fish. Is there any fish that look like tangs such as a dwarf angel or something like that that you would recommend? Offhand, I can't thing of anything. I don't know if there are any wrasse small enough for a nano tank. Most fish need more room to grow than a nano provides. If you go on the online fish stores, many have "nano" and Beginner fish sections. Maybe look there for what interests you.

14. Would 1 clown work with cardinals, firefish, goby, etc. Just without other clowns? 20 is pretty small to have many fish. It's not about the size when you get them, it's what they will become. It's also personalities... some fish get more aggressive as they age. When I got my black occ., it was less than the size of a quarter. 3 years later... he is about 4" long and the baddest boss in the tank. That fish would have outgrown a 20 in the first year. My snowflake is the smallest, also the most chill. The percula is in the middle. Pajama cardinals are chill - but they will get to about 2-3". Firefish and gobies are very skittish. Overall, the decision is yours but you will need to be careful of overstocking. That can stress the fish and tax the biofiltration capability. Make sure you provide ample hiding places.

15. Would the livestock choices I made work? see previous answer

16. How long should I cycle a tank with live and dry rock with Dr. Tims? However long it takes to get to 0 ammonia and nitrites. Your nitrate will spike towards the end.

17. But would topping off every 2 days be OK? In a nano, things change very quickly. You will have more stability if you add an ATO and top off as needed.

18. How often should saltwater fish be fed? Some fish once a day, some twice. Depends on eth fish. Of course, they always look hungry.

CMMorgan · Mar 17, 2021

Jekyl said:
All of those fish are on liveaquaria.com just check the minimum tank recommendation for any of them. Depending on size of the fish 3 or 4 is going to be the max you should have in a 20 gallon.

I agree with @Jekyl Those are some choices but you can't do all of them. 2-4 is about it. Again... look at the grown up size before committing. I have a 6 line. We call her Ruby. Many people will post that 6 lines are bullies... I have never had that experience.

miradaYf · Apr 6, 2021

LifeOfAquatics said:
Hello, I am thinking of starting a 20-gallon long reef tank soon and I wanted to ask some questions in hopes of getting answers. If you could, please label your answers with numbers so that I know which question you are responding to. Thanks in advance!

All this is for a 20 Gallon Long Reef Tank with RODI water

1. Can you house two different types of clownfish together? (i.e. black ocellaris and regular ocellaris clown (which is what I want to do personally))
2. Would you recommend anemones/zoanthids in a beginner reef tank? Do clownfish even need them?
3. What are some corals you would suggest to a beginner starting a reef tank in a 20 gallon long?
4. Best fish/stocking ideas for a 20 gallon long?
5. Would buying live rock from Petco (not from the tank, but the individually prepackaged ones) and mixing it with dry rock work in curing the rocks? If I buy live pre packaged rock from Petco, I don’t have to cure it right? I can just throw it in there?
6. I feel like this is a dumb question, would you suggest buying live rock and/or corals from Petco? What about fish? Ik dumb question but im curious lol
7. What are some good lights for corals that are budget-friendly?
8. Do I need to quarantine or dip corals or anything like that? How would I go about doing this?
9. Do you need to feed corals? I heard that most of the time not right? If I do, what should I go abt feeding them?
10. Should I get a protein skimmer for a 20 gallon long? Or is a HOB filter enough?
11. Is there a limit to CUC? Obvi I won’t overdo it like 30 emerald crabs or anything lol but like do you have any CUC stocking suggestions for me?
12. So I really like tangs, I just like the idea of feeding one and how they look, do you have any suggestions for fish that are sort of like tangs in that they are semi large, peaceful for the most part, reef safe, like seaweed (I just really like the thought of hand feeding a tang lol), and is good for a 20 gallon? Im totally cool if there isn’t, just it would be nice to have like a centerpiece fish. What abt a 29 gallon?
13. After some research, I have decided that I am TERRIFIED of bristle worms, just the way they look, the fact that they can harm you, they can kill your fish, there are a parasite, just ugh. Are there any reef safe peaceful fish/inverts for a 20 long which will kill bristle worms? Is there any way to check to see if rocks have them? Any traps or ways to get rid of them?
14. Can you house only one clownfish but other fish like gobies, Firefish, etc. just not have a pair of them, just one but with other species of fish?
15. Would 2 clownfish, 2 Cardinalfish, 1 Firefish, and 1 watchman goby along with some CUC work in a 20 long? I definitely plan to have live rock and sand and if need be, I will get a filter which is a size bigger than my tank (I.e. a 40 gallon filter for a 20 gallon tank). Would this work? If it wouldn’t work, could you tell me why and other stocking alternatives?
16. If I buy live rock from say my LFS, do I need to quarantine it or cure it? Also, if I have some live and some dry rock, can I just put that both into my tank and let the dry rock cure in there for about a month with say Dr. Tim’s One and Only (I think thats what it is called)?
17. So in my research, I found that a 20 gallon tank will lose roughly 1.75 gallons a week or .26 gallons a day. Is it OK if I top off my tank every two days manually? I am asking because I generally feed all my pets once every two days, so I could top off whilst feeding. Would this work or would it mess up the stability of my tank? Also I plan on having a tight lid like a glass lid. If I do put a glass lid, how much can I expect my average top off gallonage to go down by? As in, compared to without a lid/screen lid, can anyone estimate what the difference will be if I use a glass lid?
18. Can saltwater fish be fed once every two days?
19. Is it possible to top off every week or something like every 4 days or would it mess up my stability?
20. How often should I clean my reef tank? I normally clean all my tanks every 2-3 weeks, 3 weeks sometimes for a planted tank, 2 weeks for axolotl, but I if I am being honest rarely do once a week. I have a python system so doing it weekly is not too big of a problem, I just don’t really choose to lol and all my pest have been fine

Zoanthids are quite dangerous. Look up palytoxins before buying any kind of coral as well. Not something pet stores tell you.. and most people, even people who have had aquariums for years are unaware of this. Plenty of horror stories from people doing very simple and seemingly careful and normal things with their tank.