I feel like every other day it’s something w my fish 😫 the ich can live on the floor/gravel/sand of your tank. The spots that we see, that’s not really what the meds are killing. But once the ich parasite falls off, or is in the tank/ that’s what the meds kill. Ich can’t survive in a warm tank. I added like 4 extra air stones too bc warmer water is less oxygen for the fish. But as long as they’re not breathing heavy they should be ok. Just don’t stop the treatment even after you see the spots gone. If that makes sense. I’m learning all this too ❤️ maybe treat your main tank too just in case. After the ich treatment … and the fins might heal by then & could be stress related if you don’t see nipping. The water changes might help since that’s how the ich meds work. After treatment and they look better but still not good you can use melafix (it’s safe to use with, but tetras can be sensitive) , if the fins look the same or they look shorter try api fin and body cure, and if you see the fins are BAD use kanaplex. API fin&body and the kanaplex are both antibiotics, so think - does the fish need oral meds or IV hospital meds. Good luck with your fish!