Sudden Problems

[westonsupermanc]

I was gutted yesterday when a Mono I have had for 2 years was upside down dead for no apparent reason. Now today 2 Peppered Corydors are spiralling around as if they have swim bladder disease. So I moved 5 fish to a smaller tank and did a water test. Nitrate 0 Nitrite 0 but what has shocked me is the ammonia reading around 5mg/l guess that's why he died. I guess either I have put too many fish in the tank or I am overfeeding them. Any suggestions on getting the ammonia back to zero. I have 32 fish in there mostly small ones however the large fish are 2 Silver scats 1 Featherfin Cat 1 Picto Cat 1 Archer and 4 medium Angels. In the morning I feed them small and large pellets and in the evening 2 cubes of bloodworm and a mussel cut up. Any help is appreciated.

 

[sawickib]

How big is the tank? The only thing i could think of is do as large of a water change as possible every day until its really low or 0

 

[Lillefishy]

Monos & scats need brackish water as they mature that's probably why the mono died, it was in freshwater for too long.
As for reducing the ammonia you'll need to do several large water changes, take out as much water as you can leaving enough for the fish to stay upright then test & then do another one, it may be too late for the corys though

 

[westonsupermanc]

Thanks 75% water out of 480 litre tank now the long task of added the treated water back in bucket by bucket jes. Also gonna add big bag of shell slate as pf was lower than 5 so water very acidic. Will test again tomorrow thanks for the advice
As the local shop said when I took a water sample in for a second opinion he was astonished that the nitrate reading was over 80 but there was zero reading  for nitrite and well the ammonia was off the scale way over 8mg/l and the ph well below 5 he could not understand what I have been doing. I even bought a large external filter but cleaned it in warm water thus killing all of the good bacteria so guess tank has had to cycle again. Just hope I lose no more

 

[sawickib]

I'd say it's very good you have no nitrites, likely your bacteria is working and converting nitrites to nitrites like it should, you just don't have a large enough bacterial colony.

Warm water won't kill your colony, most likely the cholorine in it if you used tap, unless you have tap, then it would leave me to believe you added to many fish to fast.

Also after you fix this which I know you can through multiple water changes, I would suggest to keep brackish fish with brackish fish and freshwater fish with freshwater fish, it will make them all live longer and healthier that way.

Hope your tank and fish get better!