Hi,
I'm dealing with a mysterious illness in my tank and although I've been pretty iffy on adding any types of medications because of the plants, it's to the point that if fish keep dying off I'll have to consider doing something. It started with a recurrent case of ich which I think I have completely under control now, at least I've had no symptoms in three weeks, but then suddenly within the past three days I've lost a pleco and a cory. They both started showing swim bladder problems and in the case of the cory, his barbels showed internal bleeding, and died within 24 hours of showing symptoms. There is no reason that I can see for this as far as water chemistry goes, all parameters are normal and healthy and I'm doing my regular water changes. It's been suggested that I could have some kind of parasite so I was just wondering if adding malachite green and formalin will kill my plants, or what meds I could add without endangering the plants. I am going to wait until I see another fish get sick before I do add anything in case it was coincidence with the two fish that just died.