Hi all, I've been having some trouble in one of my tanks. It's a five gallon bowfront. It has a sponge filter and Seachem Fluorite Black Sand (plus a few live plants). It houses a single male betta, but he's on his last legs - he was hit by a severe case of fin rot, and I just started a round of KanaPlex today in hopes of seeing a miraculous recovery - but my main question is about my API Master Test Kit. I left my tests overnight and this morning I noticed in my ammonia test tube there's a little filmy precipitate in the bottom. I shook the bottle and it disintegrated, but perhaps the weirdest thing is that now the color in the test tube is almost rose gold. Anybody know what's going on?