Stone for Aquariums, Medium – Natural Water Clarifier and Odor Remover, Treats 15 to 40 Gallons
$27.93
Price: $27.93
(as of Mar 28, 2025 22:50:15 UTC – Details)
Product Description
Add to Cart
Add to Cart
Add to Cart
Add to Cart
Add to Cart
Add to Cart
Customer Reviews
3.9 out of 5 stars 333
4.2 out of 5 stars 1,006
4.3 out of 5 stars 19
4.0 out of 5 stars 226
4.2 out of 5 stars 2,401
4.3 out of 5 stars 299
Price
$12.65$12.65 $15.46$15.46 $15.62$15.62 $19.89$19.89 $27.93$27.93 $52.20$52.20
Dimensions (in.):
1.125 x 1.125 x 1.125 1.125 x 1.125 x 1.125, each 2.5 x 2.5 x 1.0 2.5 x 2.5 x 2.0 3.75 x 3.75 x 2.125 3.75 x 3.75 x 2.125, each
Tank capacity (gal.):
0.8–1.5 0.8–1.5, each 3–8 8–16 15–40 15–40, each
Weight (lb.):
0.1 0.1, each 0.22 0.5 1.2 1.2, each
Available in a 2 pack
✓
no data
no data
no data
✓
no data
Product Dimensions : 2.63 x 4.1 x 6.1 inches; 13.6 ounces
Manufacturer recommended age : 1 month and up
Item model number : EBSMC00105
Department : Conditioners & Additives
Date First Available : June 17, 2010
Manufacturer : ONEdersave Products LLC
ASIN : B003SOTWLI
Country of Origin : Japan
Volcanic rock containing beneficial bacteria colonies, disperse about every 30 minutes. Clarifies cloudy water and eliminates odors
Speeds up nitrogen cycle, with 100% pure bacteria in spores which germinate in early, middle and late stages, only germinating in the presence of organic waste.
Reduces need for frequent maintenance by continually replenishing beneficial bacteria for 1 and a half to two years
Safe for all fish, reptiles, amphibians and other aquatic life
Simple to use, no mess aquarium care in fresh or salt water. M size treats tanks from 15 to 40 gallons.
Customers say
Customers are satisfied with the product’s functionality and water quality. It helps clear tank water quickly and reduces nitrate levels. However, opinions vary on whether it kills fish, value for money, appearance, and smell.
AI-generated from the text of customer reviews
13 reviews for Stone for Aquariums, Medium – Natural Water Clarifier and Odor Remover, Treats 15 to 40 Gallons
Add a review

$27.93
Nattyb –
Aquarium essential!
Highly recommend. Been using these for years. It definitely needs to be used as directed, and plan your time accordingly. Rinse in chlorine-free water and soak overnight or all day in chlorine-free water. Works like a dream. Clean tank as needed, even with help from snails.I have had a stone or 2 where I didn’t think it worked but I care about my fish more than water clarity, and the water tests came up perfectly normal while using it. Cycles completed, fish-in (goldfish), within a week or 2 tops.
Wendy Palmer –
HIGHLY RECOMMEND!!!
Before and after pics and video! I am new to the aquarium hobby. I have a 75 gl tank with a few Koi fish and Plecos. After about a month my tank starting a bacterial bloom, was cloudy, and needed frequent water changes. I saw this product at Petco and thought what the heck Iâll try out after I researched it. All the reviews were glowing here on Amazon, internet and on YouTube and every tank that had one of these cleared up quick. I decided to buy this medium one as I had bought the small and wanted to see what it would do. I didnât want and substrate in my tank just for cleanliness. Literally about a week later I get home from work after 2 partial water changes both days before and my tank was crystal clear!!!! Prior to this I had a 40 gallon tank and had tons of problems with water changes and my fish dying but I was determined to get this right to enjoy fish keeping. I spoke to a local aquarium store owner and he talked me through everything such as a larger tank not being as hard as a smaller one and that the concentration of water in a smaller one is just bad because if one fish gets sick they spread it fast to the others faster. He did not mention this product I just decided to try it and boy am I glad I did!!! My water and my fish are thriving. I check my water levels daily and test the water. Since putting this stone in itâs stayed consistently the same. If youâre having trouble with a tank TRY THIS youâll be impressed. I know for koi I need a bigger tank and that is the plan or an outdoor pond.. Also take the package advise and soak for the 24 hours in non chlorinated waters. It has some bubbles that will discharge from the stone and small particles that the soaking process will clean this off of it. This will help to stop you from transferring the particles to your fishes home. Iâm thrilled I tried this project.
KdE –
It rocks!
Easy to use. Just soak overnight and toss in a pond. It lasted in my 40 gallon outdoor pond for 2 years before it got covered in algae. Took it out and let it sit in the sun a few days then resealed and added it back. 4/5 goldfish approved (with goldfish that is great odds)
Customer –
Works great
I had tried several things to get my water to clear up. In about 36 hours after adding the stone my water was crystal clear and my fish are much happier.I recommend this to anyone with an aquarium.
Chaz –
Nope!
These do not work as advertised. Iâve had aquariums all my life so I am no novice. I placed two in my 75 gallon tank and they did absolutely nothing.
kim –
I’ll give it a 3 star because my turtle loves it as a bed
I bought it and it made more of a mess than my turtle. It crumbles and leaves debris everywhere on bottom of tank, read it had to be by flowing water so i put near the filter and NOPE .just made water cloudy and particles everywhere…So had to change out the water and i set it aside in the tank (no clue why i even put if back in there after having to clean the whole tank because of it) my turtle started pushing it under his basking platform ..and fell asleep on top of it…he uses it as a bed now lol so as long as he’s happy and uses it for something i suppose its not a complete waste of money
RG –
Amazing
Have Geophagus cichlids for years and even raised their babies but always hard to maintain water and waste. Seems to always lose 1 8months to yr with Popeye and I have 2 large enheim filters each 50gal capable and I only have a 55 gal tank and water change and maintain clean tank.. They eat hardy and release waste just as much..So that was overview and now have another large male with popeye again building past 2 weeks so attacked with new substrate (3 different levels) water changed, new filter pads and continued to get worse to point heâs now hiding and just matter of days.. So I bought this rock figured worth a shot since medicine never works just waste money and stress on fish and only success with 1 over years.I know long review but worth the understanding of environment. 2 days in with this filter rock and heâs better, eyes clearing and heâs back out vibrant. Not sure how it works but for any fish lovers this is a must bio rock and I will never have a tank without! Even other fish seem happy swimming like youngsters again. Waters been clear so donât see a difference but underlining water quality must be perfect for them.Just amazing!UPDATE: want to give update since I canât believe whatâs happened and might help alot of fish lovers out there.The Cichlid with Popeye for past weeks now is just about back to normal after 4 days since adding this bio rock. I donât know if these results are typical, cleaned a particular issue in water or if it was just an added part to water change and complete filter substrate replacement or what but I have never been able to cure Popeye in 8 yrs doing the same things minus this bio rock so this is the first and in 3 days!! Heâs back swimming, eating, playing with others, eye swelling and eye fog gone! Iâm still in shock but at the least this rock can only be helpful in any tank with fish imo so hopefully it helps others.And for placement I actually suspended it ontop of a long decorative hollow tree about mid tank level so water can circulate completely around the whole rock to maximize water contact.
alex –
Good for 40gallon
Good for 40 gallon tank
Cheryl Robertson –
Seems a good acccessory itâs helping keep tank clean and clear
chantale dambrosio –
I havenât noticed any difference for my tank so I canât really say it helped or not
Lynne Irwin –
It works
Judith Ng –
Cannot use the stone as the stone is easy to fall apart into small pieces in water and my turtle is kept biting the rock. Do not want my turtle to become sick by eating the fall apart tiny pieces.
yw2012 –
Before having this magic stone, I had to change filter weekly ( filter was black and completely plugged by the end of 1 week) and water change bi-weekly. Now, the filter was clean after 1 week, and water perfectly clear by the end of 2 weeks. I have 6 good sized gold fish in each tank. thanks to this magic EcoBio-Block stone. This is THE single most efficient, and cheapest equipment for fish tank!!