Advice please re treating parasites
Several of my fish are repeatedly flashing. All the water stats are fine. I reluctantly decided to treat my main tank (as too many fish affected to use my small quarantine tank). I'm using Aquacare Anti parasite (active ingredients copper sulphate & formalin). The packaging said it was safe for all fish which I naively believed, but unfortunately my young pleco died overnight.
Some of my other fish (guppies, swordtails, mollies) are hanging at the surface
or down at the bottom. They seem to feed happily but I don't want to lose more fish. Should I be concerned or is this just an expected side effect of the meds?
I don't know how long the meds should take to work (they can be repeated after 7 days if needed), but I'd don't want to leave them in longer than necessary.
Any advice would be appreciated.
Many thanks in advance.