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Why does my fish tank light cause brown algae? What lighting is best?

Updated On September 23rd, 2025

Pet's info: Fish | Freshwater Fish

I got a lED fish light for my fish tank and I only got one light for one side so far and where the light is its growing a brown algae really bad and the other side without the light isn't. Do certain lights cause algae. If so, what lights don't and what type of lighting is the best? I have two filters in my tank and it's only one side so I dont think it would be anything else

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1 Answer

Most Helpful Answer

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Answered By Angel Alvarado, LVT

Licensed Veterinary Technician

Published on January 28th, 2020

Its the amount of light that can promote algae overgrowth. Limit lighting to 6-8 hours daily. Monitor water temp as well. Do not overfeed and remove dead/dying plant matter to also limit algae. You can remove any tank furniture and scrub them clean.

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