So confused with what is happening

[MKDean]

We have a 20 gallon Nuvo peninsula with 5 small damsels, emerald crabs, one shrimp, assorted corals, hermit crabs, nasserius snails, and one turbo snail. Woke up yesterday to one chromis, two emerald crabs and a shrimp dead. The other fish were breathing heavy, but the nasserius snails were up on the rocks instead of in the sand. I tested the water and did a water change.

Temp - 78.4
pH - 7.8
Ammonia - 0
Nitrate - 0
Alkalinity - 13.4 dKH
Phosphate - 1.76 (We have been struggling to get this down, dosing, GFO and water changes)

Throughout the day the fish breathing seemed to go back to normal, the nasserius snails went back into the sand. Then today I woke up to another chromis almost dead, laying on his side in the sand. The other fish breathing heavy and a few of the nasserius snails out again. Im lost on what to do or what is causing this. Thanks for your help!

 

[nautical_nathaniel]

What kind of source water are you using for water changes (Tap, RODI, etc.).

Do you have any algae problems?

Physically, what do the dead fish look like? Any spots, significant discoloration, injuries or other marks?

What corals are you keeping?

Do you run carbon on the tank?

 

[WVNed]

That is way too many things to keep in 20 gallons

 

[Justin_Luke]

Could be not enough oxygen in the water. What’s your flow look like in the tank?

 

[MKDean]

What kind of source water are you using for water changes (Tap, RODI, etc.).

Do you have any algae problems?

Physically, what do the dead fish look like? Any spots, significant discoloration, injuries or other marks?

What corals are you keeping?

Do you run carbon on the tank?

We us RO for top off and buy salt water from our local store. We did have an algae problem but everything has been fine for a few weeks now. The fish looked normal, maybe some redness on the gills. We have a couple chalice, mushrooms, hammer, ribbon, palythoa, acan, gsp, and duncan. We have chemi pure blue in our tank.

 

[MKDean]

Could be not enough oxygen in the water. What’s your flow look like in the tank?

We have our filter output and a 660 gph wave maker running on full power. Cleaned regularly.

 

[BestMomEver]

Nothing struck me as odd until you mentioned red gills. You may have a parasite. @Humblefish .....

 

[MKDean]

Nothing struck me as odd until you mentioned red gills. You may have a parasite. @Humblefish .....

Would this be affecting emerald crabs and shrimp as well? Making nasserius snails sit out of the sand? I’m just so confused

 

[dbjonesjr]

Could also mean ammonia.

 

[dbjonesjr]

Also why is your alk so high? What salt mix do you use?

 

[BestMomEver]

Would this be affecting emerald crabs and shrimp as well? Making nasserius snails sit out of the sand? I’m just so confused

No.... didn’t think of that. I’m stumped too. How old is this tank? Also, have you heard any popping noises? If you bought real, living live rock you could have a mantis hitchhiker. They will kill anything. Especially slow moving crabs and snails. They also like sleeping fish. They are ambush predators and hunt primarily at night.

 

[lapin]

Just a thought. Your algae was supplying oxygen and using up the excess ammonia in your tank. Overstocking can cause excess ammonia that your tank can not process quick enough. Now that the algae is gone you have a problem.

 

[Captain Quint]

Also why is your alk so high? What salt mix do you use?

+1. The Alkalinity - 13.4 dKH alarmed me as well. How long has it been this high, please? It would certainly be good to get ~12 or a bit lower.

 

[dbjonesjr]

+1. The Alkalinity - 13.4 dKH alarmed me as well. How long has it been this high, please? It would certainly be good to get ~12 or a bit lower.

I had a problem recently with bad calibration fluid. Therefore my salinity was high (1.030) causing my other elements to be high as well. I don't know of a salt mix that actually mixes this high at standard salinity. Either way I would try and get this down.

 

[Dom]

Nothing struck me as odd until you mentioned red gills. You may have a parasite. @Humblefish .....

I agree. That and the long list of inhabitants and corals. As previously stated, there is more in the tank than can be supported.

1. Are you using live rock in the tank?
2. How old is the tank?
3. Did you quarantine the items you've placed in the tank BEFORE placing them?

Also, be very guarded with the advice you get from local fish stores. We are in a day and age where brick and mortar stores are struggling to compete with the on line industry. They push quick installation and stocking advice to get the money flowing in to the business.

I recommend that the next time you buy their water, run all of your tests on it. You may be surprised at the results you get.

Dom

 

[Jon Fishman]

That is way too many things to keep in 20 gallons

I admit I chuckled at "5 small damsels" Even if they didn't grow, I wouldn't put that many in a 20g

Are there more Chromis' in the tank? Other fish other than the 5 + 1 dead?

 

[Dom]

I admit I chuckled at "5 small damsels" Even if they didn't grow, I wouldn't put that many in a 20g

Are there more Chromis' in the tank? Other fish other than the 5 + 1 dead?

I think that someone with a lot of experience would be able to support the tank at those stocking levels. But we need to know more about what equipment is being run in the tank. At the very least, I'd hope that there is some method of skimming going on.

 

[BestMomEver]

The OP said that he/she had done water changes. I’m stumped as to how dkh could get that high unless the salt mixed that way or a test kit was wrong. What test kits are you using? API are notoriously inaccurate. I recommend Red Sea, Salifert, or Hannah checkers. How are you testing Salinity? Maybe recalibrate or look into a new unit.

Many people are eluding to fish stocking. Typically you want to try to stay in the range of one inch of adult size fish to every 3-5 gallons of water. This is different than freshwater. So, chromis will reach about 3 inches long and if you had five, that’s 15 inches of fish. Way too high. In a 20 gallon, you could safely keep three chromis. Take into consideration that chromis swim a lot. If you got a more sedentary fish like a Goby, you might could increase the number fish you have. Fast swimming fish use more energy. More energy requirements = more food. More food = more waste. I will buy baby fish that get too large for my system and when they start getting too big, I will return them to the LFS and get another baby fish. Example.... tangs.... I have a 60 cube and have a tiny yellow tang. Sixty gallons is way too small for a tang. Pretty soon he’ll go back to the store and I’ll get another baby. Also, chromis are very peaceful with other fish species, but not each other. I had always heard that if you buy six, you’ll end up with one or two. I started with six and now have two. They just slowly disappeared. Have no clue what happened to them, but judging from the way they chase each other, I’m betting they killed each other off.

I’m guilty of over stocking. Over stocked tanks mean more diligent maintenance. But, I have tried to be smart about it. For instance, my clowns stay pretty close to one area. The Firefish stays in his little space. I’ve tried to avoid having fish that swim so much that the run into each other. My tang is really the only one that is a free swimmer.

What is killing your snails, etc is a mystery. Snails and crabs do add to your bioload but only a little. People think that because they are clean up animals that they are not waste makers. They are. I wish I could help more.

 

[beaslbob]

Sounds to me like lack of plant life like macro algae.

I would add macro algaes in an in-tank refugium and add cheapo lights like a spot led plant light to get the algae thriving.

The decrease in co2 and possibly ammonia plus increase in oxygen should help the situation.

my .02

 

[Captain Quint]

........ I’m stumped as to how dkh could get that high ....................

+1.

I was kind of wondering if pH was perhaps being chased and too much Reef buffer was being added which will definitely increase the dkh?