Catfish dieing after pwc

[Tyler2354]

I have young "petricolis" catfish in my African cichlid tank. Yesterday evening I did a 30% water change and cleaned out my canister filter. I rinsed all the pads in aquarium water and everything. Added cichlid salt to the tank after I filled it back up, I did everything that I usually do when doing a cleaning. All fish are fine except for my catfish. I don't think they are true petricolis but they were sold to me that way. I think they are lucipinnis cats. Anyways, I wake up this morning and there are three dead or dieing, and now about lunch time there is another dieing. I checked my water parameters and they are 100% good. I have no idea what happened.
Help please

 

[k.jonesy]

if your parameters are all good and everything was done the same as usual, it could have been the shock of changing temps or when dumping water back in the tank it could have really freaked them out. My zebra catfish died this way after a 50% water change and gravel vacc. Could possibly be a toxin aswell. if you havnt already, add some activated carbon to remove. Even if its not a toxin carbon will help remove meds and odours so its really a win win.

 

[Tyler2354]

It's just so strange having them die like that. Because they were all fine before. And then that night and morning after, they died.