EcoBio-Block EcoBio-Stone with Beneficial Aquarium Bacteria, Small

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About This Item

Details

  • Clears cloudy aquarium water and helps eliminate odors via beneficial bacteria found in volcanic rock and green cement.
  • Helps reduce your tank’s hands-on maintenance needs for up to 2 years per stone.
  • EcoBio-Stones help speed up the natural nitrogen cycle in your tank.
  • Can be used with all fish, reptiles, amphibians, and other aquatic life.
  • Effective in freshwater, brackish, or saltwater tanks.

Instructions

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Frequently bought together

Questions & Answers

17 Customer Questions

How would I know if and when the EcoBio-Stone needs to be replaced?

Answer by Chewy • Jun 07, 2018
The EcoBio-Stone should be changed once the water starts becoming cloudy. The block can last from 2 days up to 3 months in the tank.

Do you still need a filter with this or does it replace a filter?

Answer by Chewy • Apr 22, 2018
This rock will benefit your tank in numerous ways however you still need a filtered pump. This helps with other chemicals to be removed from your tank and keep your fish safe.

Can you use this for aquatic turtles

Answer by Chewy • Apr 23, 2018
This product can be used with aquatic turtles.

Does this go in the aquarium or does it have to be placed in a filter?

Answer by Chewy • Apr 12, 2018
It is not necessary to place this Block in a filter. To use, rinse off the stone with chlorine-free water, soak overnight and add to your tank, preferably near an air source. If you have an airstone, place it near the airstone. Once immersed in water, beneficial bacteria in the stone will start to propagate and disperse into the water approximately every 30 minutes.
Reviews
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4.0
Rated 4 out of 5 stars
69 Ratings
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36 Customer Reviews

Rated 5 out of 5 stars
By Meghan on Oct 26, 2025

Seriously amazing

I have been trying everything to get my kids fish tank from being green all the time. I was cleaning it weekly, conditioning the water, bought live plants, etc

I have been trying everything to get my kids fish tank from being green all the time. I was cleaning it weekly, conditioning the water, bought live plants, etc. Nothing worked, and a lot of the stuff I did not want to buy because it was really toxic and I honestly felt uncomfortable having it aroubd the house with the kids. I came across this and figured why not, it cant hurt. I followed directions, put in the tank and nothing happened for about 2 weeks. Then all of a sudden it became more and more clear by the day. Now water is crystal clear and I 100% recommend this product. I never leave reviews, but for those struggling like I was, I wanted you to know it's not a waste of your money.

Rated 1 out of 5 stars
By Karen on Aug 25, 2025

Smelled

Did not like this rock for the aquarium. It had a very strong odor and soon after my fish began to die. Not sure if it’s related but would not purchase again

Did not like this rock for the aquarium. It had a very strong odor and soon after my fish began to die. Not sure if it’s related but would not purchase again

Rated 3 out of 5 stars
By marisa on Jun 6, 2025

I can't really tell if it is working

I add seperate bacteria because I don't see any difference with the stone

I add seperate bacteria because I don't see any difference with the stone

Rated 5 out of 5 stars
By Zaida on Apr 13, 2025

Very porous

Helps keep the tank clear and algae under control.

Helps keep the tank clear and algae under control.

Rated 1 out of 5 stars
By Sarah on Mar 15, 2025

Didn’t Work

never bubbled, and I soaked it overnight. waste of time/money

never bubbled, and I soaked it overnight. waste of time/money

Rated 5 out of 5 stars
By Lisa on Feb 6, 2025

Hard Worker

I believe the block is helping my freshwater aquarium water.

I believe the block is helping my freshwater aquarium water.

Rated 5 out of 5 stars
By Debbie on Nov 24, 2024

Worked so fast!

It was working in my aquarium quickly & shipping with Chewy is always fast!

It was working in my aquarium quickly & shipping with Chewy is always fast!

Rated 1 out of 5 stars
By Maria on Aug 11, 2024

Didn't work

Maybe the 2 pack I got were defective bc I put first one and then the other in my 20 gal freshwater tank and I've seen no clearing of the water after a month.

Maybe the 2 pack I got were defective bc I put first one and then the other in my 20 gal freshwater tank and I've seen no clearing of the water after a month.

Rated 5 out of 5 stars
By Stephanie on Nov 12, 2023
Top 1000 Contibutor

EcoBio-Block works well

It helps to keep my turtle tanks cleaner and is safe, easy to use and not expensive.

It helps to keep my turtle tanks cleaner and is safe, easy to use and not expensive.

Rated 4 out of 5 stars
By Kevin on Mar 30, 2023

Easy and not ugly

They seem to do what the claim, and they look good in a tank. I have one in with my turtle and he lays on it.

They seem to do what the claim, and they look good in a tank. I have one in with my turtle and he lays on it.