20G Nano Reef

[KeremAltinbasak]

Hello everyone after a long time :)

A lot has happened, but I can't remember much. Those who died, those who survived, we're still going!

You can see the additions in the video :)
We're healthy and well now!

 

[KeremAltinbasak]

I decided to take a natural approach to my never-ending nitrate issue and built a small refugium inside my sump.
I created an extra section and now run a 6500 K light for about 16–18 hours a day, letting the chaeto do its job.


I’m also hoping this setup will help boost my pod population and add some biological filtration alongside the mechanical one.


What do you think? Any suggestions or improvements are welcome!

 

[TheNative192]

following along!

 

[KeremAltinbasak]

Here’s how my sump is currently set up:
Water first passes through filter floss (fiber), then goes through activated carbon, Siporax, and Matrix.
From there, it flows into the protein skimmer section, then into the new mini refugium, passes through the heater chamber, and finally reaches the return pump section.
It’s a continuous loop, keeping everything in motion.

 

[KeremAltinbasak]

When we finally got to the final stage, I added the anemones :)
I added the second shrimp, and they've become a pair, and one of them is even carrying eggs now.

The firegoby was added, but the damsels and bluetang are so annoying that he only leaves the back left corner when he's feeding and spends the rest of the day lying down.

I feel a little bad for him, but I think he'll get used to it in time.
I separated half of the cheton into a separate tank, placed it with a waterfall filter and light. I also added 4-5 large pods I caught from the sump. I'm going to try my own pod culture. Maybe I can keep them and use them as food for the fish :) Then I plan to add a mandarin to the tank.

That's the current situation.

 

[KeremAltinbasak]

Here are the results of my latest tests: My nitrate is still high.

Salinity: 1025
Temperature: 24.6
pH: 8.1
Nitrate: 50
Phosphate: 0.02
KH: 8.46
Magnesium: 1350
Calcium: 410

 

[KeremAltinbasak]

Hey everyone,
I wanted to share my small pod-breeding setup and get some feedback from the community.

I’m culturing copepods + amphipods mainly to support a future Mandarin Dragonet in my main reef tank.
Here’s my current setup:

Small glass tank

Large ball of Chaetomorpha

A gentle waterfall/hang-on-back filter (low flow)

Weekly water changes using water from my display tank

3–5 drops of phytoplankton and zooplankton every 3–5 days

A tiny pinch of flake food occasionally for the amphipods

Lighting: simple refugium LED

No predators inside (only pods)


I constantly see amphipods and baby pods everywhere in the chaeto, on the glass and rock rubble — so the culture looks healthy.
Every 2–3 days I swirl the chaeto and add a cup of pod-rich water to my display tank to seed it.

Questions for the community:

1. Is this routine enough to sustain a long-term pod population for a Mandarin?


2. Should I add more rock rubble or leave it as is?


3. Would you recommend ditching the HOB filter and going air-stone only, or is gentle flow better?


4. Any tricks to harvest copepods more efficiently?


5. How often do you recommend splitting the culture?



Any advice or improvement ideas are welcome.
Thanks in advance!

 

[KeremAltinbasak]

Yes, as a final development, I removed the separate pod tank I had set up because, for some reason I couldn't understand, they started to melt, and before things got worse, I harvested all the pods and transferred them to the main tank.

And now I thought it was time and added the mandarins.

I'm still transferring the pods I caught from the sump to the main tank with the lights off. I hope it will be enjoyable, but as soon as I put them in, they were attacked by damselfish; hopefully they'll give up.

 

[KeremAltinbasak]

Hello everyone!
I wanted to give an update on the latest situation. Some very, very interesting things have been happening in the tank lately.

First, the good news: I added a Mandarin. It seems healthy for now, and I haven't run into any issues. I’m continuing to seed the display tank with pods from the sump. At first, the damsels harassed it, but it recovered within a day or two and seems to be accepted now.

However, the general vibe has turned extremely aggressive over the last week. I lost both of my shrimp. I found their molts first; the first shrimp was caught in the wavemaker, and I found it being eaten by the anemones. It likely molted, was vulnerable, and couldn't escape. My second shrimp got stuck in the wavemaker as well—I noticed just in time to rescue it while it was still struggling, but it died shortly after and was consumed by the fish and nassarius snails.

Then there's the Firegoby. It was doing great and looked very fit lately, but this wave of aggression got to it too. Its fins and tail were completely shredded. I managed to get it out of the tank before it died and rehomed it to someone else.

The strangest part? One of my two Talbot's Damsels beat the other one to death overnight; I found the carcass the next morning. Even the Blue Tang and Yellow Wrasse have joined in on the bullying. The tank has gone absolutely crazy for reasons I can't explain.

In a "fight fire with fire" move, I decided to add a medium-to-large Splendid Dottyback, hoping its tough personality might bring some order back to the tank. As soon as it went in, the Blue Tang attacked it and nipped off a piece of its dorsal fin. It’s currently hiding, so I’m not sure of its status yet! :D

I have no idea what to do next, but things are definitely getting wild in my reef. I’ll keep you posted on any further developments.

 

[Project1004]

It’s getting wild because you are putting too many fishes in the tank. Your tank is too small to host 5-6-7? Fishes. And that tang is too big for the tank my guy. We should try to give them an environment where they can prosper. Stop adding fishes for awhile.

Also re-arranging rockscapes do help with aggression too.

 

[Tahoe61]

The issues you are describing are the result of over stocking the system and your choice of fish. In an already over stocked tank the addition of another fish is a recipe for disaster.
A Blue Tang in a 20 gallon is not best practice. Passive Fire Fish are not going to be able to stand up to Damsels.
It's not surprising in the least that these issues are arising and sadly will result in the demise of one or more of the fish. The system is not going crazy, it's the expected outcome of poor stocking choices.

 

[Ben's Pico Reefing]

To many fish/to large of a fish. When fish are small they seem like they will work in a small tank. In fact initially a small tank at a tangs young age can have more space than most people will in larger when fully grown. Example, I small 4 inch tang in a 40g vs it fully grown to 14 to 16 inches in a 90 or 120 gallon. And while peaceful fish can coexist in crowded tank as well, usually there is still territory disputes. I have kept things before I shouldn't have and we all may have a time or two. Some limits can be based on opinion. But the tang unless just temporary or for treatment shouldn't be in a 20. Especially after it reaches about 2 to 3 inches. I have seen them com in as small as half inch roughly.

Damselfish are also just jerks. Some just aren't as big of a jerk as others lol. Sometimes a large tank they are still bullies. The is one species called springer that seem to be not as aggressive and certain clownfish such as oscilarious or percula can be a little less aggressive or just as aggressive. Chromis which are similar are usually only jerks to each other. But with anything different people will have different experiences as every fish can behave differently.

Edit, I would remove the tang, yellow wrasse I saw in pic, dottyback and damsel. Just keep firefish. And clownfish. You can keep manderin but try to switch it over to frozen or other prepared foods. Might need to be slowly transitioned. If you cant get it to switch think about rehoming or getting one that is raised on pellet or frozen already. Create a stock list if you get rid of mandarin of what you would like or ideas and community can help. Maybe even with fish you didn't think about. There is some really cool smaller fish.

 

[KeremAltinbasak]

It’s getting wild because you are putting too many fishes in the tank. Your tank is too small to host 5-6-7? Fishes. And that tang is too big for the tank my guy. We should try to give them an environment where they can prosper. Stop adding fishes for awhile.

Also re-arranging rockscapes do help with aggression too.

Thank you for the detailed feedback. Everything was going smoothly until recently, but something seems to have triggered this sudden aggression in the tank.

I've read your comments carefully. I’m aware that the Blue Tang has grown very quickly; it’s definitely outgrowing the space, and I’m planning to remove it as soon as I can catch it. While I do have plans to upgrade to a larger tank soon, I know that process will take some time.

I'll be looking for a solution in the meantime to restore balance. Thanks again for the advice!

 

[KeremAltinbasak]

The issues you are describing are the result of over stocking the system and your choice of fish. In an already over stocked tank the addition of another fish is a recipe for disaster.
A Blue Tang in a 20 gallon is not best practice. Passive Fire Fish are not going to be able to stand up to Damsels.
It's not surprising in the least that these issues are arising and sadly will result in the demise of one or more of the fish. The system is not going crazy, it's the expected outcome of poor stocking choices.

Thanks for your comment. I am aware of the points you raised. If you look back at my previous posts, you’ll see that I sometimes struggle to set limits for myself when it comes to this hobby.

I certainly have no intention of causing any distress to the fish; I try my best to take good care of them, but sometimes these things happen. As I mentioned, I realize the Blue Tang is getting too large, and I will be taking care of it soon.

 

[KeremAltinbasak]

To many fish/to large of a fish. When fish are small they seem like they will work in a small tank. In fact initially a small tank at a tangs young age can have more space than most people will in larger when fully grown. Example, I small 4 inch tang in a 40g vs it fully grown to 14 to 16 inches in a 90 or 120 gallon. And while peaceful fish can coexist in crowded tank as well, usually there is still territory disputes. I have kept things before I shouldn't have and we all may have a time or two. Some limits can be based on opinion. But the tang unless just temporary or for treatment shouldn't be in a 20. Especially after it reaches about 2 to 3 inches. I have seen them com in as small as half inch roughly.

Damselfish are also just jerks. Some just aren't as big of a jerk as others lol. Sometimes a large tank they are still bullies. The is one species called springer that seem to be not as aggressive and certain clownfish such as oscilarious or percula can be a little less aggressive or just as aggressive. Chromis which are similar are usually only jerks to each other. But with anything different people will have different experiences as every fish can behave differently.

Edit, I would remove the tang, yellow wrasse I saw in pic, dottyback and damsel. Just keep firefish. And clownfish. You can keep manderin but try to switch it over to frozen or other prepared foods. Might need to be slowly transitioned. If you cant get it to switch think about rehoming or getting one that is raised on pellet or frozen already. Create a stock list if you get rid of mandarin of what you would like or ideas and community can help. Maybe even with fish you didn't think about. There is some really cool smaller fish.

To many fish/to large of a fish. When fish are small they seem like they will work in a small tank. In fact initially a small tank at a tangs young age can have more space than most people will in larger when fully grown. Example, I small 4 inch tang in a 40g vs it fully grown to 14 to 16 inches in a 90 or 120 gallon. And while peaceful fish can coexist in crowded tank as well, usually there is still territory disputes. I have kept things before I shouldn't have and we all may have a time or two. Some limits can be based on opinion. But the tang unless just temporary or for treatment shouldn't be in a 20. Especially after it reaches about 2 to 3 inches. I have seen them com in as small as half inch roughly.

Damselfish are also just jerks. Some just aren't as big of a jerk as others lol. Sometimes a large tank they are still bullies. The is one species called springer that seem to be not as aggressive and certain clownfish such as oscilarious or percula can be a little less aggressive or just as aggressive. Chromis which are similar are usually only jerks to each other. But with anything different people will have different experiences as every fish can behave differently.

Edit, I would remove the tang, yellow wrasse I saw in pic, dottyback and damsel. Just keep firefish. And clownfish. You can keep manderin but try to switch it over to frozen or other prepared foods. Might need to be slowly transitioned. If you cant get it to switch think about rehoming or getting one that is raised on pellet or frozen already. Create a stock list if you get rid of mandarin of what you would like or ideas and community can help. Maybe even with fish you didn't think about. There is some really cool smaller fish.

Thank you so much for your kind message and for sharing your knowledge and experience with me. I really appreciate it.

I want you to know that I’m taking your advice seriously. I’ve actually thought about doing a complete species overhaul myself, but catching these little rascals is no easy task!

I’m also considering rearranging the rockwork, but I’m a bit worried about spiking my already high nitrates and upsetting the balance in such a small volume. I’m also trying to figure out where I could even place extra rocks if I added any. Maybe I’ll come up with a solid plan and reorganize eventually.

But you're right my fish have definitely grown, and I need to get ahead of the situation before it becomes a bigger problem.

 

[Ben's Pico Reefing]

To many fish/to large of a fish. When fish are small they seem like they will work in a small tank. In fact initially a small tank at a tangs young age can have more space than most people will in larger when fully grown. Example, I small 4 inch tang in a 40g vs it fully grown to 14 to 16 inches in a 90 or 120 gallon. And while peaceful fish can coexist in crowded tank as well, usually there is still territory disputes. I have kept things before I shouldn't have and we all may have a time or two. Some limits can be based on opinion. But the tang unless just temporary or for treatment shouldn't be in a 20. Especially after it reaches about 2 to 3 inches. I have seen them com in as small as half inch roughly.

Damselfish are also just jerks. Some just aren't as big of a jerk as others lol. Sometimes a large tank they are still bullies. The is one species called springer that seem to be not as aggressive and certain clownfish such as oscilarious or percula can be a little less aggressive or just as aggressive. Chromis which are similar are usually only jerks to each other. But with anything different people will have different experiences as every fish can behave differently.

Edit, I would remove the tang, yellow wrasse I saw in pic, dottyback and damsel. Just keep firefish. And clownfish. You can keep manderin but try to switch it over to frozen or other prepared foods. Might need to be slowly transitioned. If you cant get it to switch think about rehoming or getting one that is raised on pellet or frozen already. Create a stock list if you get rid of mandarin of what you would like or ideas and community can help. Maybe even with fish you didn't think about. There is some really cool smaller fish.

To many fish/to large of a fish. When fish are small they seem like they will work in a small tank. In fact initially a small tank at a tangs young age can have more space than most people will in larger when fully grown. Example, I small 4 inch tang in a 40g vs it fully grown to 14 to 16 inches in a 90 or 120 gallon. And while peaceful fish can coexist in crowded tank as well, usually there is still territory disputes. I have kept things before I shouldn't have and we all may have a time or two. Some limits can be based on opinion. But the tang unless just temporary or for treatment shouldn't be in a 20. Especially after it reaches about 2 to 3 inches. I have seen them com in as small as half inch roughly.

Damselfish are also just jerks. Some just aren't as big of a jerk as others lol. Sometimes a large tank they are still bullies. The is one species called springer that seem to be not as aggressive and certain clownfish such as oscilarious or percula can be a little less aggressive or just as aggressive. Chromis which are similar are usually only jerks to each other. But with anything different people will have different experiences as every fish can behave differently.

Edit, I would remove the tang, yellow wrasse I saw in pic, dottyback and damsel. Just keep firefish. And clownfish. You can keep manderin but try to switch it over to frozen or other prepared foods. Might need to be slowly transitioned. If you cant get it to switch think about rehoming or getting one that is raised on pellet or frozen already. Create a stock list if you get rid of mandarin of what you would like or ideas and community can help. Maybe even with fish you didn't think about. There is some really cool smaller fish.

Thank you so much for your kind message and for sharing your knowledge and experience with me. I really appreciate it.

I want you to know that I’m taking your advice seriously. I’ve actually thought about doing a complete species overhaul myself, but catching these little rascals is no easy task!

I’m also considering rearranging the rockwork, but I’m a bit worried about spiking my already high nitrates and upsetting the balance in such a small volume. I’m also trying to figure out where I could even place extra rocks if I added any. Maybe I’ll come up with a solid plan and reorganize eventually.

But you're right my fish have definitely grown, and I need to get ahead of the situation before it becomes a bigger problem.

I would syphon the sand as you pull out the rock. This will prevent any spikes if there is detritus and stuff trapped under. This would also be a good time to catch what you need to remove. You could also setup the rockwork outside tank to how you want then place in tank. I like the negative space currently. Allows room for maintenance and cleaning but can add some branching pieces as well that will keep some of the negative swimming space and provide a barrier, but still allow more structure.

We all have that impulse to buy what we know shouldn't lol and make mistakes. Since you are upgrading, you could find a larger temp tank to throw everything in until you are setup, or just another tank for temp. Something used is fine.

 

[TheNative192]

Hello everyone!
I wanted to give an update on the latest situation. Some very, very interesting things have been happening in the tank lately.

First, the good news: I added a Mandarin. It seems healthy for now, and I haven't run into any issues. I’m continuing to seed the display tank with pods from the sump. At first, the damsels harassed it, but it recovered within a day or two and seems to be accepted now.

However, the general vibe has turned extremely aggressive over the last week. I lost both of my shrimp. I found their molts first; the first shrimp was caught in the wavemaker, and I found it being eaten by the anemones. It likely molted, was vulnerable, and couldn't escape. My second shrimp got stuck in the wavemaker as well—I noticed just in time to rescue it while it was still struggling, but it died shortly after and was consumed by the fish and nassarius snails.

Then there's the Firegoby. It was doing great and looked very fit lately, but this wave of aggression got to it too. Its fins and tail were completely shredded. I managed to get it out of the tank before it died and rehomed it to someone else.

The strangest part? One of my two Talbot's Damsels beat the other one to death overnight; I found the carcass the next morning. Even the Blue Tang and Yellow Wrasse have joined in on the bullying. The tank has gone absolutely crazy for reasons I can't explain.

In a "fight fire with fire" move, I decided to add a medium-to-large Splendid Dottyback, hoping its tough personality might bring some order back to the tank. As soon as it went in, the Blue Tang attacked it and nipped off a piece of its dorsal fin. It’s currently hiding, so I’m not sure of its status yet! :D

I have no idea what to do next, but things are definitely getting wild in my reef. I’ll keep you posted on any further developments.

Thank you so much for your kind message and for sharing your knowledge and experience with me. I really appreciate it.

I want you to know that I’m taking your advice seriously. I’ve actually thought about doing a complete species overhaul myself, but catching these little rascals is no easy task!

I’m also considering rearranging the rockwork, but I’m a bit worried about spiking my already high nitrates and upsetting the balance in such a small volume. I’m also trying to figure out where I could even place extra rocks if I added any. Maybe I’ll come up with a solid plan and reorganize eventually.

But you're right my fish have definitely grown, and I need to get ahead of the situation before it becomes a bigger problem.

If you plan to upgrade get a large 40 gallon tub and put half fish in it with some rocks from the main tank. Add some new rocks and add an air pump.

I will be honest the way you are adding fish is accustom to dog fighting tbh. Saying you are impulsive or just can’t control yourself is not reasonable. Even if you buy a larger tank tomorrow it will take you time to cycle it and even then it won’t surprise me if they are all dead from fighting by then.

 

[Project1004]

Easiest and best way to catch the fish is to simply drain the water to very low and just scoop them out. Much less stress on the fish and less mess made in the tank.

Seems like your tank/fishes were on the borderline of overstocking and caused aggressions and many casualties….

 

[Tahoe61]

I certainly have no intention of causing any distress to the fish; I try my best to take good care of them, but sometimes these things happen.

I sincerely appreciate your concern for the tank inhabitants.
What's happening is the expected outcome when you combine the fish those choices and the size of the tank. Fish have no where to flee to.
Going forward you should be more proactive in seeking assistance here.
Each one of us has made mistakes. Ideally we share those mistakes and move forward to provide the best care for our fish and inverts.

 

[KeremAltinbasak]

I would syphon the sand as you pull out the rock. This will prevent any spikes if there is detritus and stuff trapped under. This would also be a good time to catch what you need to remove. You could also setup the rockwork outside tank to how you want then place in tank. I like the negative space currently. Allows room for maintenance and cleaning but can add some branching pieces as well that will keep some of the negative swimming space and provide a barrier, but still allow more structure.

We all have that impulse to buy what we know shouldn't lol and make mistakes. Since you are upgrading, you could find a larger temp tank to throw everything in until you are setup, or just another tank for temp. Something used is fine.

If you plan to upgrade get a large 40 gallon tub and put half fish in it with some rocks from the main tank. Add some new rocks and add an air pump.

I will be honest the way you are adding fish is accustom to dog fighting tbh. Saying you are impulsive or just can’t control yourself is not reasonable. Even if you buy a larger tank tomorrow it will take you time to cycle it and even then it won’t surprise me if they are all dead from fighting by then.

Easiest and best way to catch the fish is to simply drain the water to very low and just scoop them out. Much less stress on the fish and less mess made in the tank.

Seems like your tank/fishes were on the borderline of overstocking and caused aggressions and many casualties….

I sincerely appreciate your concern for the tank inhabitants.
What's happening is the expected outcome when you combine the fish those choices and the size of the tank. Fish have no where to flee to.
Going forward you should be more proactive in seeking assistance here.
Each one of us has made mistakes. Ideally we share those mistakes and move forward to provide the best care for our fish and inverts.

First of all, I would like to thank everyone individually for their feedback. Since many of you shared similar points, I wanted to provide a collective response.

I’ll start by saying that you’re right—I have made some mistakes, but they were never intended to cause distress to my fish. If that were my goal, I certainly wouldn't be here seeking advice. On the contrary, I added them because watching these beautiful creatures brings me so much joy. If you look back at my first photos, you’ll see the Blue Tang was only about 2-3 cm when I got it. In a year, it has grown to 6-7 cm, maybe even more. My wife and child love it dearly, which is why I’ve kept putting off the move, but I realize now it has become essential.

When I observed the tank yesterday, things seemed to have calmed down. I think the initial pressure was due to the newcomer, but yesterday everyone was swimming freely. However, I know this doesn’t mean I can just sit back and do nothing.

I am planning to upgrade to a larger tank, but not immediately. I have a long process ahead with home renovations and new furniture, so this tank will have to continue for a while longer. Because of this, I’ve decided to rehome the Blue Tang and, if I can catch them, the Wrasse and the Damsel as well. I might consider adding a smaller, more peaceful Wrasse species later on, as I find them very beneficial.

I’ll keep sharing updates and progress here. Regarding the rockwork and hiding spots, I have a few projects in mind. I’ll check with my local fish store for suitable rocks and consult with you all again before making any changes.

Thanks again to everyone. We all learn through our mistakes.