API CRYSTAL BIO-CHEM ZORB SIZE 10 Aquarium Filtration Media Cartridges for API SUPERCLEAN 10 2-Count Box

Perfect for the little pump in our 2.5gal tank. Be sure to read the directions about rinsing thoroughly before adding into the tank... I missed this on my first one and it left the water cloudy. An easy fix, and they are priced well so I chalked it up as a lesson learned. It has been great since then!

So much easier and slightly cheaper than buying at local pet stores.Usually lasts my 6 gal 1 goldfish tank about a month. I usually have to rinse it out a couple times within the month as it does get clogged up and restricts water flow. You can tell when your filter makes a funny noise. Otherwise these are great filters and last longer than other brands I’ve purchased in the past. Keeps my tank clear and clean.Make sure to rinse it for at least 1 minute before putting it in. There’s a lot of charcoal dust that comes off.

If you keep shrimps and setup a new tank with new driftwood and/or botanicals, I would suggest using these for a couple month during and after cycling. The organics and hydrogen sulfides released by the driftwood and anaerobic bacterias for months even after cycling is complete could be overwhelming for the shrimps and kill them as they are more sensitive than fish (happened several times to me until I actually understood the cause, as all parameters I could test were good - pH, KH, GH, Ammonia, NO2, NO3, PO4, K, Fe, Copper, Chlorine, Oxygen. I use distilled water remineralized with Salty Shrimp Minerals so I now my Ca:Mg:K ratios are good and no hidden heavy metal or unwanted element in the water). I tried Seachem Purigen (didn't work), hydrogen peroxide treatment (in case it was a bacterial infection - didn't work), tried heavy water changes (didn't work). When it happened for the 3rd time in a (cycled) new setup with brand new driftwood and ghost shrimps started to be in distress and dying (fish were completely fine), I went across a thread about this resin that was stating to work against toxic gases. I put the survivor shrimps in quarantine to recover while run this resin for a month in the display tank, moved 1 shrimp back into the tank while running a new cartridge of API crystal bio-chem zorb for another month for observation. As everything looked fine I moved the rest of the group back into the display tank, switched to Purigen after that and problem seems to be resolved. That topic doesn't seem to be talked about much online, maybe I am using a particularly large amount of wood in my scapes, but that's my 2 cents...

It works great but it is to small the width of it should match the filter and it doesn't.. One of the ones I used tore open cause it was not sealed correctly. Also the pack is like a width 1"1/2 to smaller than the filter.I've heard of trying to save money on material book hey come on.

This works as an excellent replacement for the Koller size S filter in our Koller 5 gallon tank. The matching Koller filters are all out of stock or overpriced, so I was happy to discover that this filter fits perfectly into the pump that came with our tank. It also seem to be of a higher quality. But as other reviews have said, be sure to rinse it thoroughly before use.

Bought these as they were the replacement filters for the round cylinder aquarium on Amazon. They really do keep the tank clean. I washed them by hand every week but replaced completely after four weeks. Has very little algae (close to none) on sides. Very pleased with this as when I've had other tanks it was constant clean up. The water is crystal clear with these. Haven't lost a tiny goldfish yet, so I think it's keeping them healthy.

Recently purchased a 5 gallon tank. It came with a filter included and this is the replacement cartridge for it. So far so good. It does a pretty good job of keeping the tank clean. I usually do a full water change once a week and this filter allows the water to remain clean until my next water change. I wash out the cartridge every time I do a water change and replace the cartridge every 2 or 3 weeks. So far these replacements have worked perfectly. Very happy with it. Will continue to purchase.

My fish tank is very clean. I am satisfied even though I bought the wrong size lol. Other than that, great filter!

Funcionan muy bien, lo que si recomiendo es que vean bien su filtro para que quede a la perfección ya que son pequeños y en mi filtro lo uso, aún así funcionan, pero el tamaño puede incomodar a otro cliente

I put a huge piece of rosewood in my axolotl tank and within 24hrs my 240ltrs of water looked like iced tea. Within 24 hrs of putting just 1 of the pouches in my filter the water is back to crystal clear. I dont know how long the pouches will last, it definately wont be as long as my wood is going to leach tannins but are totally worth the money if you dont like stained water. I was initially concerned adding chemical filteration would effect my axies but theyve not reacted in any way. Theyre eating fine, growing well and still have beautifully coloured gills and its been in a few weeks. Have to add axolotls have very porous skin so any nastyness would easily kill or harm them and other than prime on water change days I have no other chemicals in my aquarium. I will be buying again.

I order this online via amazon because these filters save me about $7 than at my local pet store. Its 18 on amazing and 24 at PetSmart. They work great and keep my fishtank clean.

El agua de la pecera perfectamente limpia

Waters crystal clear even after a 2 week holiday!