1. Purchasing fish that feed off of algae is a good plan to take care of an algae problem in your aquarium. You could also try cutting back the amount of lighting in the aquarium or get an algae treatment chemical to take care of any algae problems.
2. You should always research the different types of fish you are going to be housing together. Certain fish can be extremely aggressive and cannot be paired with other fish of different temperaments.
3. You should always purchase the correct lighting setup for your aquarium. Doing this will make the habitat much better for the fish and plants in your aquarium.