Petco Text Logo
Petco Pet Logo
  • Two Easy Ways to Start Earning Rewards!

    rewards header
    Become a member today!
    Members-only pricing and offers, personalized care notifications, Vital Care points back on every purchase and more!
    Petco Pay LogoBecome a credit card member today!

    Earn 2X Pals Rewards points at Petco
    when you use Petco Pay!

    APPLY NOW
    Learn More About Petco Pay Benefits

My fish tank has algae. Is it safe to clean the water and filter?

Updated on September 23rd, 2025

Pet's info: Fish | Betta | Male | unneutered | 8 months and 29 days old

Is it safe to change my fish’s water and filter? The algae got in up in the filter and in the water.

1 Answer

Most Helpful Answer

Angel Alvarado, LVT

Answered By Angel Alvarado, LVT

Licensed Veterinary Technician

Published on April 19th, 2019

Yes, you can rinse filter media (the sponge) using tank water. This will preserve beneficial bacterial populations in the sponge. The plastic filter parts can be rinsed and scrubbed using tap water.
Perform a partial water change, no more than 30% total volume, using conditioned water that is temperature matched.
To limit algae overgrowth, do not overfeed, limit lighting to 8-10 hours daily and monitor water temp. If possible, turn up filter flow to get the water moving. Algae thrives in slow moving water. Do this only if your fish are not affected by stronger currents.
Vote Icon1Pet Parents found this answer helpful

Smart Picks for Smart Questions

Have A Vet Question?

Book an appointment with the pros – our expert vets are here to help.

Share

Styled arrow button