Yote is right, only use frozen foods. Flakes and pellets = algae.
If you do regular water changes, you probably won't need to dose any of those things except calcium. Salts contain a balanced amount of the trace elements and minerals that you need. Doing a water change not only removes waste from your tank, but it adds back the minerals and elements that get depleted over time. The rule of thumb is that if you don't have a test kit to show you're deficient, you don't need to dose for it. If you just dose things that you think you need without testing first, it's easy to overdose your tank.
For the fish food, most people (myself included) use Selcon.