I'm pretty new to Bettas - right now Sashimi is in a 1 gallon tank, we'll probably upgrade to a 2.5 gallon in a few months. I change his water once a week, sometimes twice if it looks cloudy. I do a 100% water change since the tank is small - when we get the 2.5 gallon tank I'll start doing 50% changes. My question is, the water gets cloudy and this white looking stuff looks like it is growing on the top level of water and also on his little castle thing he hides in. When I change the water it has an icky smell. I've been just rinsing out the rocks/castle and tank sides with hot water and using a sponge scrubber to get off the slick feeling stuff. But can I disinfect the tank/castle/rocks with something before I put the new water in? What should I use? I saw someone on TV use salt as a natural disinfectant, but not sure if this is safe for a freshwater fish (obviously they rinsed it really well before they filled it up again, but still). Anyone got suggestions or pointers? Otherwise, does it sound like I'm doing everything right so far?