Dropping Like Flies

[star182]

Did a water change Monday. Nothing different from usual. Readings after change were nitrite 0ppm and ammonia 0ppm. Yesterday I found 2 dead endlers and 2 dead platys. Nothing else. Noticed a few dead platys earlier, took em out, checked the levels and the ammonia has risen to 0.25ppm and nitrite to 0.25ppm. Guessing that is from the dead fish I found (they were stuck behind the filter). In the last hour I have lost 14 fish and they keep dropping. One of my corydoras is currently dying slowly. His fins all went pink, his gill slits have gone red and the rest of his body is slowly turning pink. My other 2 dead corydoras had clouded over eyes (they were all super active last night as usual). There is no aerosol ever sprayed in my room (it has 5 tanks in it ). There was a strange film over the top of the water before they all started dropping and the water has turned cloudy over night. The majority of the remainder are gathered at the filter, all grouped up. A few are swimming, a couple of others hovering at the top of the water. The platys have been slowly dropping off the last couple of weeks but they have been eating each other alive I bought a new corydora about a month ago, just over. He was quarantined in the shop. He showed no sign of illness. I've had the platys for a month and a half, they came from a friend's tank. They've had them for years and there were no health problems with them. Anyone got any ideas at all? ;/ pH is 7.4

 

[nehpets81]

Ouch, sounds nasty. I've no idea what is happening to your fish but maybe a 100% water change would be a good idea at this point in case there was something wrong with the water last change?

 

[star182]

Ouch, sounds nasty. I've no idea what is happening to your fish but maybe a 100% water change would be a good idea at this point in case there was something wrong with the water last change?

I'll do that tomorrow. I don't think i'm going to save the remaining fish if I'm honest, no matter what I try Hoping the LFS can pick something up tomorrow when I take my water in! Well gutted I changed one of my axie tanks just after the trop tank and there's no problems with that so don't think it's the change

 

[Juggler75]

Could be an outside contamination from aerosols or something. There are many poisons that won't show up during routine water tests of the sort we have access to. Full or close to full water change could help if it was. Or did the LFS pick anything up or suggest anything else?

 

[HayzH]

Are you sure you dechlorinated? Maybe you forgot?

 

[mark4785]

Obviously just a water quality issue here. I think from past reading, I've learned that if a gaseous aerosol gets into the water, the water usually provides the conditions for that gas to produce a certain type of fungus which then kills the fish. If there is no fungus in the filter or walls of the tank, IMO, the water quality is causing problems, not an external variable. Ensure you're waiting a full 5 minutes when testing your ammonia and nitrite as I suspect your levels are over 0.25 ppm for fish to be dieing off at that frequency.

I'd definitely recommended doing a 100% W/C as anything less will not remove sufficient ammonia/nitrite. Put the fish and filter media in a fully dechlorinated container (put 2-3 times more dechlorinator in than recommended) containing a heater. Re-fill the tank up with fully dechlorinated water; preferably use Aqua Safe has it protects the fishes slime coat and put 2-5 times the recommended dose into the water. Re-integrate the fish slowly; put them in a sandwich bag containing water from the container and float this at the surface of the aquarium water for 20 minutes, putting 30-50ml of aquarium water in every 2-3 minutes.

 

[star182]

Thanks for the replies My filter sponge came to the end of its life so in short it caused a massive algal bloom, the fish died from lack of oxygen. I've bought a new filter (I was using the old fluval 4 and couldn't find sponges for it) and added some API clearer recommended by the LFS. It's cleared up, done a water change and have about 5 fish left.

 

[N0body Of The Goat]

How do you mean, "filter sponge came to end of its life"? Often filter making companies will write something like "replace [certain sponge] every six weeks" or whatever, but in reality most filter sponges should last years harbouring ammonia and nitrite processing bacteria. The only layer that is worth replacing every week or two is the filter floss and that can be made much cheaper than the official replacements by buying a massive sheet of "Koi filter wool" or alike that is than cut into suitable pieces.

Have you put any of the old filter sponges in this new filter? If not, you are not "fish in cycling" and you will need to do at least 50% water changes daily, being very careful with food quantities and doing twice daily tests for ammonia and nitrite (doing immediate >50% water changes of either reading reaches 0.25mg/l or higher).