Problem with a new Angelfish

Question

I have a new 120 gallon tank. Its been set up for about three weeks. The first week I cycled it, and the last two weeks I have had 6 mollys in it as test fish. So everything was fine and yesterday I went To PetCo to buy 6 angelfish. I woke up this morning, and they were all fine. They had been in the tank mabe twenty hours. I went to work for two hours and when I can back... One fish is now floating around the tank and can barely keep himself up in the water. And I cant even find one the the other angels. I went upstaires to look for a seperate tank for the barely alive angel because I have turned off all filtration because the agel was being sucked to the filter, or the undergravel system would launch him across the tank. When I came back I also couldnt find him... Two missing fish. I found that badly hurt fish under a rock... Seriously have no idea how he dug under there, but he managed. And im still looking for the other fish. Any ideas on how I can help this poor fish while I look for the other one?

Answer 1

Do you have a test kit?  Have you tested your water?  You say that it's cycled, but 3 weeks to cycle a 120 gallon tank sounds awfully fast to me.  Mollies are a lot hardier than angelfish.  I would want to get that water tested.  If you have another tank, I would fill it up with fresh, conditioned water and put those angelfish into it while I get the water from the 120G tested for ammonia and nitrites.

Answer 2

Problem number one is buying fish from Petco.  They are poorly bred imports, if half make it you are doing ok.  Find an independent shop that buys fish from local breeders.  You will have much more success.

  That few fish in that size tank should not be any sort of problem, even with a newer tank, as long as you are keeping up on water changes.  Minimum of 25% weekly.