# Unstable fish in a stable tank



## expresiva (Sep 6, 2011)

My husband has a 56 gallon tank that has been established since January. He had 2 yoyo loaches, 2 ruby sharks, 4 cardinal tetras, 3 silver tipped tetras, 1 marble hatchet, and 1 zebra danio, one Betta plus a very small algae eater in the tank, and the chemistries of the tank have been stable for a long time. Last week he put 2 marbles, 5 danios and 4 cardinals to the tank. They did fine at first, everyone was active, interacting with the others, and eating. After a few days, though, all the new fish started showing up dead, looking fine in the morning and dead a few hours later. We've since lost ALL the new fish (except the new danios and none of them are looking good, including the old one), our original hatchet just died and one of the original cardinals. Did he overload the tank with too many new fish? Or are we missing something else?


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## majerah1 (Oct 29, 2010)

Most likely that is the case.Its best to add a one or two at a time,otherwise there is a spike in the ammonia and usually that will take them out.

Also Its always best to quarantine any new fish before adding to your existing tank,in case they have ich or other nasties.This way your current fish dont run a risk of diseases from the new ones.


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## susankat (Nov 15, 2008)

Yes its best to add just a few at a time. Also you should quarantine new fish at least a couple of weeks, You could have possibly brought in something with the new fish.


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## joeyhatch11 (Jul 27, 2011)

I had the same problem last week. I had my 40 breeder runninng fine with 3 fish and added 2 fish and 3 small crabs. Within 2 days I had a huge ammonia spike resulting in 2 dead crab and 1 dead puffer fish. The remainder of the fish have been placed in a new tank while the 40 gets back in controll. From there I will add the fish back 1 at a time. But didnt think it would have that kind of effect on the tank that quickly.


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## joeyhatch11 (Jul 27, 2011)

Have you been able to get your tank back in order? I'm having the biggest problem with my ammonia and it seems no matter what I do it wont come down. Any suggestions?

So far I've added, Tetras AmmoniaSafe, SafeStart (beneficial bacteria) AquaSafe Plus (to condition tap water for changes) and I've even added API AmmoCarb and AmmoChips to my canister filter system, all of which have done nothing to the ammonia issue. It started off the charts at over 8ppm but now are at a steady 4 and hasn't moved in a week.


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## NeonShark666 (Dec 13, 2010)

Check the water quality parameters at your TFS and in your tank. If they are extremly different, this can cause fish deaths. High Nitrates, big ph differences or big hardness differences are possible reasons for your fish deaths. Always introduce new fish gradually to your tank water.


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