1. Make sure you ask plenty of questions when you are buying accessories or fish for your aquarium. The salespeople are there to help you, and should be able to handle any concerns you have when buying items for your aquarium.
2. Catfish sometimes require freshwater as juveniles and then as they get old they will need a more brackish environment. Make sure you read up on your catfish to learn what its needs will be when it gets older.
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.