I have 2 goldfish (each no longer than 3", excluding tail) in a 30 gallon hexagon tank. It has been up and running for around a month or so. I have 2 airstones in the tank, and a whisper HOB filter. I do weekly water changes and gravel vacuuming (should 3 gallons be enough per week?). I know goldfish are dirty fish, but for some reason, my ammonia is EXTREMELY high (around 8.0, if not higher). My Ph is around 6-6.5. I've tried almost EVERYTHING I can think of to get my ammonia down, and my Ph up. What kind of water should I be using in water changes (tap or distilled)? Should I restart my tank? Or is it just something i'm going to have to deal with while having goldfish? Any help is GREATLY apprecated.