1. Only use medication in your aquarium when you are out of other options. You should use a separate tank to medicate sick fish as some medications can have harmful effects on healthy fish.
2. You should be sure to rinse out all of the materials you are going to be placing in the aquarium with water. Do not use soap or detergents, soap can cause toxic results for the fish in your aquarium. Just rinse the equipment with distilled water.
3. It is a good idea to perform a frequent water change and cleaning schedule. Changing the water in your aquarium will keep it clean for the fish that live in the aquarium. Keep a full stock of the water treatment chemicals you will need for this purpose.