Tetra Algae Control Pond Fountain Block Water Treatment, 6 count

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About This Item

Details

  • For containerized ponds only
  • Limited to use for backyard or homeowner ponds and water fountains
  • EPA approved
  • Not for use with live plants
  • Safe for fish but not for use in non-ornamental ponds

Instructions

Questions & Answers

5 Customer Questions

I have a 10 gallon fountain that needs a nonclorine product to control the algae. And something that will not damage the plants below the fountain when splashed on. Will this Fountain Block be safe for the plants below the fountain?

Answer by Chewy • Jan 10, 2018
This product is not intended for use with live plants.

Can this be used to prevent algae in pet water fountains?

Answer by Chewy • Apr 13, 2018
This product is not recommended for use in drinking water.

I have a small water fountain (not part of a pond) that occasionally the dogs sneak a drink of water out of. Would I be able to use this to control the slightly cloudy water and beginning stages of green guck?

Answer by Chewy • Aug 15, 2018
This treatment has not been tested for safety if dogs drink the water, it would not be recommended.

Is this safe for duck pond?

Answer by Chewy • Jun 19, 2025
This product has not been tested on duck ponds and is not recommended. The product is specifically designed for ornamental fish ponds and water gardens, not for ponds frequented by waterfowl.
Reviews
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4.4
Rated 4.4 out of 5 stars
68 Ratings
Terms & Conditions

33 Customer Reviews

Rated 5 out of 5 stars
By David on Dec 24, 2025

Small fountain algae control

One block in a small water fountain under 6 gallons keeps the water algae free and lasts for weeks. Highly recommended.

One block in a small water fountain under 6 gallons keeps the water algae free and lasts for weeks. Highly recommended.

Rated 5 out of 5 stars
By Robin on Dec 28, 2025

Excellent!

These work the best for keeping fountains clean

These work the best for keeping fountains clean

Rated 5 out of 5 stars
By Susan on Sep 26, 2025

Great product

It keeps my fountain clear and makes maintenance easier

It keeps my fountain clear and makes maintenance easier

Rated 5 out of 5 stars
By Lynne on May 17, 2025

Just 1 pod per month and my algae and my fountain is gone!

When I was searching for something to get rid of the algae in my pond without being harmful to my cat that likes to drink from it. I found Tetra algae control and

When I was searching for something to get rid of the algae in my pond without being harmful to my cat that likes to drink from it. I found Tetra algae control and it is amazing! Love it!

Rated 3 out of 5 stars
By martha on Aug 11, 2025

clear water

These are quite helpful to keep my fountain clear. Doesn’t harm birds

These are quite helpful to keep my fountain clear. Doesn’t harm birds

Rated 3 out of 5 stars
By William on Jun 28, 2025

The blocks were much smaller! But cost the same.

The bigger blocks last longer.

The bigger blocks last longer.

Rated 5 out of 5 stars
By John on Oct 23, 2024

Easy to Use

While nothing prevents open water from gathering debris and growing algae, these blocks are easy to use and really help to slow the growth of green gunk. I highly

While nothing prevents open water from gathering debris and growing algae, these blocks are easy to use and really help to slow the growth of green gunk. I highly recommend them. That's why I subscribed to regular shipments a couple of times per year.

Rated 4 out of 5 stars
By Barbara on Nov 21, 2024

Keeps my fountain clear of algae.

I only wish that Tetra made "smaller" blocks that didn't require 30 gals of water/block. My fountain isn't THAT large.

I only wish that Tetra made "smaller" blocks that didn't require 30 gals of water/block. My fountain isn't THAT large.

Rated 5 out of 5 stars
By Jason on Oct 17, 2024

Great product

I have a small water fountain in the back yard and I put one of these in it each month and it keeps the algae from forming fairly consistently.

I have a small water fountain in the back yard and I put one of these in it each month and it keeps the algae from forming fairly consistently.

Rated 5 out of 5 stars
By Margaret on Aug 22, 2024

Fountain Rescued

We were having to drain and scrub our 3 tier fountain multiple times a week due to algae and the unrelenting California sun and our wild bird friends. This product

We were having to drain and scrub our 3 tier fountain multiple times a week due to algae and the unrelenting California sun and our wild bird friends. This product is amazing. I now have it in both my large and small fountains and my bird baths.