Poly-Bio-Marine for Fish Aquarium - Works for Freshwater and Saltwater Fish Tanks - Filter Aquarium Media Pads - 3-Pack of 4in x 8in Pads

I combined IOAOI PuriResin with Poly-Bio-Marine, so I couldn't tell you which one is the most effective honestly, but combined, they are working wonders on my 75g. Overnight, my water is crystal clear. I have fancy goldfish and admittedly my 75g is a bit overstocked. It has very heavy filtration (fx2, AC50, TF40, two of which were on an older smaller tank, and just added an AC110 to replace the TF), but it's not enough on its own to keep the water from being color tinged. Despite having no problems with algae and using UV filtration, the water always gets a clear green tinge just from the bioload. The filters keep it fairly clean, but cand stop the coloration. Adding the IOAOI PuriResin with Poly-Bio-Marin is helping clean that up. My other tanks don't have the coloration issue, but I'm going to add it to a couuple others that I think could benefit for other reasons and see how it does!

This filter media is really amazing! It filtered out all of the tannins that were making the water brown and also stopped the brown algae from reforming. Love it

This stuff has been a game changer in regards to the maintenance of our freshwater tank. My son has a 10 gallon freshwater tank and I was having to change the water every few weeks or change out the filtration substrates every few weeks but one of the staff at the local aquarium shop suggested I use this. I don't know how it works but it filters out harmful chemicals and organic material from your tank and keeps the tank clean for much longer. I place a small strip (1/2 inch thick) of it in the filtration system and change out weekly. It turns color to indicate the filtered contaminate. It's not very expensive and it will last at least a couple of months depending on the size of your tank and filtration needs. fHighly recommend.

Best filters on the market by far! Some aquarium places I've been to carry these and sell them for 15 bucks for on so this 3 pack is a great deal cheaper... these filters helped me when I realized you cant get replacements for my filter kit that came with my tank... also I have well water and struggled with acidity so had to use sachem neutralizer to stabilize it and these took all the bad out of the water and the phosphates etc out of the water caused by the sachem product and helped me stabilize my tank. They also help with natural waste and ammonia! I have a slightly over stocked tank so added air stones and switched to these products and I have no issues! I do a water change and vacuum every two months and replace this when I do it. Keeps my tank crystal clear and balanced! Best product ever!

This came highly recommended by Rachel O'Leary (queen of nano fish and inverts) so I ordered some and promptly cut off a postage size square and dropped in all of my tanks except for one I was medicating. Having read the back, I knew it would take out the meds. The back says dark brown is for Tannins/Humic acid and light tan progressing to dark brown is for organic wastes. So, a couple days later, I see that the squares are this brownish color. Now, I wonder how much of the Tannins are being removed? And if it gets dark brown, I guess that's when the Nitrates would be high and time for a water change anyway. I guess I was thinking this was something I could leave in my tank, but I may have misunderstood some of what Rachel was saying and/or how she was using it. I certainly don't want Tannins removed as I put leaves and wood in their to increase Tannins. I just thought I could use it as an indicator for when something bad was going on in the tank. Yet, I'm rereading the back and it says extends time between water changes. So, maybe I just use it as a guide right after a water change and then take it out, unless I want it to absorb nutrients and then leave it in. The only part then, that is still somewhat confusing (although it has been a long day for me and it could just be my brain) is the light tan progressing to dark brown registering Tannins AND Organic Wastes. Am I missing something? I will have to look up if Tannins are considered Organic Wastes. I guess they are organic so... Anyway, I might not have purchased the 3 pack if I'd realized this, although I can see that if I were going out of town, then it would be good to extend the time for a water change... Update: Only an FYI really... Does not work well for inserting inside a HOB as it just simply becomes "used" up in a day really, just from regular levels of Nitrates (~20ppm). I would suggest trying it in a HOB on a tank with much lower bio load like the one on my tank with only shrimp and dwarf corydoras.

I have used these for 30 years now. Great for aquarium emergencies when your fish are stressed by poor conditions. Also good when you have been lazy on water changes, or just when you want crystal clear water. A bit expensive, but worth it. You should always have some on hand for when things get bad. Have used in fresh and salt water--works well with both. Color changes to know when exhausted.

This filter is fantastic!! I don’t put it in my cannister filter - I just cut a piece off and drop it right in the water in my freshwater aquarium. It works great and helps me buy some time if I need to do a water change but don’t have time to do it right away. I like to use it directly in the water so I can “see” whats going on by the color it turns. I also use it the same way if I need to remove medication. One thing to keep in mind tho is if you’re adding ferts or minerals, the package says to wait 12 hrs before putting it in. I usually only use it before water changes or after meds so don’t have much personal experience about this except that it will remove Seachem Excel if you use it at the same time. I can’t say enough great things about this product. It’s a valuable item to have in my arsenal for my aquarium. Plus Amazon offers it at a much better price than my LFS.

It’s Real hood product for aquarium filters