While everyone's idea of essential products varies, starting with the basics helps you create a happy and healthy aquarium. Many fish-keepers use the following products: Water conditioner. Clarifier. Biological booster. Power filter. Charcoal filter pads. A simple fish care routine can be as basic as adding a conditioner and clarifier at every water change. You'll want to keep a filter running to add vital oxygen to your tank and help clear out debris and odors. With a range of items to choose from, Instacart allows you to easily save time shopping for fish care products.