I decided that before I go buy a larger tank for goldfish, I'd like to set my 5 gal back up. I had a betta in there before who died of an unknown illness, and the tank has been empty over a year. There is a ton of general grime and hard water scale. What would be the best way to clean it? Also, I'm trying to decide what to put in it. The filter is fairly powerful and I had a hard time getting the current still enough for a betta, so I'd like to do something different. I've read that 6 neon tetras and a snail can be put in a 5 gal. Does that sound feasible? Any other suggestions?