The only chemcial i use(and i don't even use it weekly) is my de-chlorinator. I don't throw in all those rubbish chemicals/products thats say you need them to have a perfect setup or to prevent this or that. You're only going to mess up your water chemistry. Don't treat for a disease thats not there or you'll just waste money and stress your fish out. Keep your water as simple as possible. Mess with your water and it's going to mess with your fish imo.
It's much easier to achieve frozen live foods than live foods and your fish will gobble frozen foods up just as easy.