dead fish

[allen]

i have a problem, the other day most of my fish died out of the blue.
i lost a yellow tang, a clown tang, 3 chromis, 2 damsels, 3 cleaner wrasse and all my shrimp, 3 cleaners and 2 peppermint. i checked all the water perameters and everything is good there, cal was a bit low 7.9

my two clowns showed no signs of problems and none of the snails or crabs died, also the 2 urchins are still good. any ideas what may be the problems. tank has been set up for about 1.5yrs and

 

[TylerHaworth]

Size of tank, any other changes? Anything else out of the ordinary?

 

[allen]

tank is a 77 gal with about 120lbs of live rock, prisim skimmer two 405 fluvel can filters and 8 tube t5 light fixture and no changes in 3 weeks, thats when i added the cleaner wrasse. and nothing for months before that

 

[allen]

oh ya i also have some colt coral, pom pom zanias, zoos, a brain coral, a orange suncoral, star polyps and 1 anamone

 

[allen]

ph was 7.9 cal 380 no ammonia or nitrates ro water used

 

[BigAl07]

It sounds like some type of contaminant in order to kill that much over night. I'd suggest some HEAVY water changes in addition to running a large amount of carbon ASAP.

 

[Cloudburst2000]

IMHO, that tank seems to be waayyy over-stocked. I don't know if that could have had something to do with the partial crash. Possibly that last addition over-loaded the tank causing a crash? I mean he has 3 chromis which get to be about 4" so that is about 12" of fish there, 2 damsels which get to about 3" so that is 6" of fish there, 3 cleaner wrasses which get to about 5" so 15" there. Those fish alone add up to 33" of fish in a 77 gallon tank. And that's not even including the yellow tang, clown tang, the two still living clown fish, and the five shrimp. Is it possible that the system just hit max capacity and went kablooey?

And I hope that clown tang is a juvenile. A full grown clown tang can reach over a foot long. A 77 gallon tank isn't big enough. I think they require 125g or 150g tanks minimum (can't remember which).

 

[allen]

thanks for the input. i'll let you know how things go

 

[allen]

all the fish were still small, the largest being the yellow tang but he was only about 4" so possible but don't think it was over stalked

 

[DaveK]

There are two problem areas likely to cause loss of all your fish.

The first is some sort of external poisoning. This could be from spilling something into the tank, or spraying for bugs, or anything else that might get into the tank.

The second is a loss of power and everything suffocated due to lack of oxygen.

In either case the advice given by BigAl is excellent, many large water changes and carbon filtration.

 

[allen]

thanks again guys for the input, i'll do some mass water changes and change up some filter, thanks again

 

[sjsoto]

The second is a loss of power and everything suffocated due to lack of oxygen.

i was just going to ask the same thing, i loss a tang due to lack of oxygen, i didnt have a powerhead in tank and the only flow was from return pump, return pump went down and so did my fish...