Instructions
Move the aquarium as far from windows as possible. Close blinds and drapes during the day to reduce the amount of sunlight entering the room. Use the aquarium light only when necessary; a tank that is lit for more than eight hours a day can experience excessive algae growth.
Monitor the behavior of the fish to determine if you're overfeeding them; all food should be consumed within five minutes. Quickly dispose of any unconsumed food, as the decay of food results in increased algae-promoting nutrients in the water. Remove any dead fish from the aquarium immediately for the same reason.
Replace a quarter of the aquarium's water every month to remove excessive nutrients (this is the minimum recommended rate, and some fish communities require more frequent changes).
Remove rocks and ornaments regularly for thorough cleaning. Place them in boiling water for several minutes and then scrub off any algae when they cool.
Adjust the outflow rate of filter systems if noticeable splashing occurs; less water contacting the light hood means less algae growth there. Keep the aquarium's water level high to prevent splashing from the height difference between the filter and the water surface.
How to Stop Algae From Growing on the Light Hood in My Aquarium
One of the most annoying places to find algae growing in a fish tank is on the surface of the light hood. Its presence diminishes the light, detracting from the appearance of the aquarium; and its position stops water-distributed anti-algae chemicals from reaching it, necessitating manual removal. Algae cannot be eradicated from an aquarium, only reduced, so the only ways to limit this growth are to control the overall algae levels of the aquarium and stop water from splashing the light hood.