[roark fishies]

If it is true fin rot Melafix won't help it at all. At least it never helped mine. Try a combo of Mela and Pimafix (Pimafix is a little stronger I think). Yes, remove your carbon for the entire treatment because the carbon takes the med right out of the water over time. I think the treatment should last about 4 days but it's been awhile since I used either meds. The directions on the bottle should tell you how long. Your water will start getting cloudy looking during treatment and as far as I know this is normal. Neither of these meds should affect your good bacteria you just gained through cycling.

I don't *think* these meds will hurt any of your fish but I'm not sure. Wait for some more responses. Someone correct me if I've given wrong info.