My 2 FH died. A millenium dragon and a red snakeskin. I don't know if the disease was just too fast killing the fish or I just treated them too late. My other FH, a golden one is still struggling, but it's still pretty active and eats well...although its fins seem to be eaten slowly by something. someone told me it's an itch or something. My FH that died are covered by something rough and white on their bodies. Will that kind of disease can kill a fish fast. I'm treating the remaining one with some salt and melachite green (I think, that's the name of he med.) I also have a red dragon which is very healthy. Can a put some drops of that medicine in my tank even though my FH on that tank is healthy... Just for killing some bacteria, in case there are some. I don't wanna lose my first and favorite FH.
:mecry:

Verry sorry that I have replied so late. My apologies if your fish has suffered in the time while waiting for a reply.

I suppose u keep your fish in a community tank?

Obviously, there is something wrong with your water parameters. That's why it is a matter of time before your final luohan gets sick too.

That disease is called cottonwool, or some call it ich. It will kil within 3 days after full outbreak of disease.

If your current flowerhorn has it, take the other one out first and put him in a hospital tank. The water in the main tank is contaminated, and u will have to do a 60% water change first. Treat the current sick lh in the main tank. Malachite green is fine, but dont overdose. Add salt and repeat it every 2 days.