1. 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.
2. You should keep the temperature in your aquarium constant. Constant change in the aquarium can be dangerous for the fish in your aquarium. Keep a quality heater and accurate thermometer to ensure that the water stays stable for the aquarium.
3. Provide plenty of places for your aquarium animals to hide. Studies have actually shown that the more places a fish has to hide, the less likely they are to do so! Hiding spots also provide safe spots of refuge for smaller fish in the aquarium