[MarcusRogers23]

I fed my fish the night before and everyone ate. Then I wake up the next morning with more than half of them dead or dying. I have a 150 gallon tank with a 1' eel maybe a couple inches bigger, a harlequin tusk, sailfin tang, emperor angel, bicolor angel, koran angel. All the angels are juvenile and are about 2-3 inches. I panicked and did a water change. As of now my water parameters are ammonia:0, nitrite: 0, nitrate: 20
I know the nitrate is a little high but I don't think thats what killed my fish overnight. There are no corals btw and as of now the only survivors are the eel, sailfin tang, and the koran angel. Everyone else is dead. Any help or ideas on why they died overnight would be greatly appreciated. Thank you!
Here is a pic of the sailfin... His skin is whitening and I am not sure if that is due to stress or something else: http://i66.tinypic.com/2a76dg5.jpg

 

[VWD]

How mature is the tank?



Nitrates didn't kill them, Did you use any chemicals, carpet fresh or other household products in same room as tank or sump?

 

[ChiWing]

I agree with Vinnie, nitrates aren’t going to do that. If it wasn’t an outside agent, then I’m going to bet just one of them died and the resulting ammonia spike overnight was what did in the rest.

 

[MarcusRogers23]

How mature is the tank?

Nitrates didn't kill them, Did you use any chemicals, carpet fresh or other household products in same room as tank or sump?

the tank has been running for over 3 years... I recently just does the tank with prazipro... I am now realizing I dosed with tablespoons instead of teaspoons but I was reading other forums and said that their fish did not die from an overdose. And no chemicals were used in the same room.

 

[MarcusRogers23]

I agree with Vinnie, nitrates aren't going to do that. If it wasn't an outside agent, then I'm going to bet just one of them died and the resulting ammonia spike overnight was what did in the rest.

One fish dying will cause an overnight ammonia spike in a 150 gallon? I have had fish die and never had an immediate ammonia spike.

 

[VWD]

after reading about prazipro you are correct on overdosing. But with normal dosing they recommend increasing water movement because of the depletion oxygen. By over dosing the amount I imagine it would even deplete the oxygen even more.



JMO it had something to do with the treatment. I'm not an expert on the medication , but just from reading and the sudden lost of fish. Maybe someone else will chime in

 

[Geoff]

i am also leaning towards an O2 thing. the biggest critters seemed to have died. eels are a bit odd, they can handle some crazy strange levels.

i am not sure how PraziPro works, but it doesn't sound like a C source, so not sure how it would have caused this, but it seems kind of smoking gunish.

were the dead fish pale in color?

G~