1. It is a good idea to clean your aquarium with a soft wash cloth and warm water. The soft cloth will not leave scratches on the inside of your aquarium and will remove any unsightly stains.
2. You should never used any alcohol to clean the inside of your aquarium. Alcohol can pose health problems for the fish in your aquarium.
3. It is never a good idea to add shells from the beach into your aquarium. Introducing shells raw from the beach can add harmful bacteria and potentially new creatures to the aquarium.