Stone for Aquariums, Small - Natural Water Clarifier and Odor Remover, Treats 8 to 16 Gallons

I believe that this stone has worked wonders, according to the many positive reviews I have read.However, I read a few reviews that say that their fish died. That was enough to scare me offfrom trying this stone, even though I bought it. My first experience with a fish tank (I'm a beginner),the fish died off from Ich. Now I have had red fantail goldfish and zebra danio alive and healthy formonths, and so I don't want to take any chances of killing them off. The pet store worker told methat the tank cloudiness may be a result of too many water changes. So, although this product seemsto work for many reviewers, I am going to pass on it.

As you can see in the before and after photos, this rock works. I was skeptical because I have a 40 gallon tank and it was really cloudy but after just one day it was already way better. After 5 days, it is completely clear again. I’m blown away. Totally worth the money.

just a great item to have if you have fish tanks or any kind or aquatic aquariums.

I've used this in both my larger cold-water tank (30 gallons) and in my 10- and 6-gallon tanks. These are great at maintaining water clarity, reducing ammonia, and helping keep the tank inhabitants happy. Yes, they are kind of ugly, so I hide them behind foliage in my planted tanks. And yes, you will still need to properly cycle and maintain your tank water quality. Overall, though, I find they do a really nice job of reducing the frequency of water changes and keeping the tank water crystal clear.These are particularly good at clearing up cloudy water in planted tanks with substrate, and I've used them extensively that way to strong effect.

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 he’s 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 he’s better, eyes clearing and he’s 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 don’t see a difference but underlining water quality must be perfect for them.Just amazing!UPDATE: want to give update since I can’t believe what’s 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 don’t 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!! He’s back swimming, eating, playing with others, eye swelling and eye fog gone! I’m 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.

I use this in a 55 gallon aquarium with goldfish and snails. After soaking the stone, then placing it in the aquarium, it takes a few days to see a difference in the water, but it works. It also seems to provide calcium for the snails as I found a noticeable difference for the better in shell quality after adding this to my tank. Yes, there is some residue that appeared on my glass after the rock was placed in the tank, but I was able to wipe that away and it did not return. The rock is also extremely large, not very attractive, and difficult to hide in my aquascaping. Due to the size of my tank, they recommend having two of these in my tank, but that just won’t work with my set up (it would take up too much space and be an eye sore). The packaging says these last 1-2 years, but I found one in my 55 gallon tank lasted about 5 months. So, I give it 4 stars because it works and the benefits are worth having one in the tank, but it’s ugly and oversized.

This thing works beautifully use to clean tank at least once a week now with this stone water stays clean for over a month VERY HAPPY

Well it worked for a little while. It did get red of the smell and it keep it clear for a little while. It last about 3 months before it stop working. I would recommend it if you don't mind it working for a little bit.

Seems a good acccessory it’s helping keep tank clean and clear

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!!

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.

I haven’t noticed any difference for my tank so I can’t really say it helped or not

It works