.25 ppm shouldnt kill your fish, it would just be uncomfortable. I'm thinking you didnt match the water temp of the new water with the temp on the tank. that could have resulted you putting a lot of colder water into the tank and shocking the cories. they dont seem to like huge water changes in general (x>60%) It's just a gues though so dont take my word for it. It's also likely that you will have some bad nitrite readings in the next two week. just thought you should know this and that its even more likely to harm your fish than this ammonia spike. (which isnt really a major one at all)
You did the right think with the shark.
Of course im not saying do nothing because the .25ppm is normal =/
Smaller regular water changes might help.
You did the right think with the shark.
Of course im not saying do nothing because the .25ppm is normal =/
Smaller regular water changes might help.
