mold

Hello, I've bough a 70ish gal from some dude who didn't understand what he was doing. He drilled 2 holes at the top "frame" of the fishtank to pass some cables for the light. He didn't seal anything. The condensation leak inside the "frame" (because the hollow inside the frame was easily...

I have a 10 gallon tank with a simple filter. one guppy, one sunburst platy, and one mickey mouse platy. something fuzzy and white are appearing on my fish and my 1 in. pleco just died this morning. I just recently started keeping a tank and need some help, please.