1. It is generally a good practice to purchase the largest aquarium that you can actually afford. A larger aquarium will be less susceptible to quick changes in the chemistry, and will offer much more stability.
2. It is not recommended to keep your aquarium where it receives direct sunlight. Exposure to direct sunlight can upset the balance of the aquarium and can raise aquarium temperature levels. It is best to keep your aquarium in a place where you can control the lighting.
3. 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.