1. You should keep plenty of water testing kits for your aquarium. Testing kits can measure the levels of harmful and beneficial chemicals in the aquarium. You will need these testing kits for the frequent water changes for your aquarium.
2. Having a quarantine tank on hand is a very good practice to use if you frequently buy new fish. The quarantine tank will weed out any sick fish that could possible get into your aquarium and cause harm to the other inhabitants.
3. In larger aquariums, you should put a few scavenger fish in the tank. Scavenger fish will help to clean up left behind food and wastes from the other fish in the aquarium. This is a good eco friendly way to keep your aquarium clean.