AquaClear BioMax Biological Material Remover Inserts – Replacement Chemical Filter Media for 50 Gallon Tank

I used this for my small betta tank. I thought this was small but actually it was very big. Anyway, I still use this product and so far working really well. My water looks staying clean.

I used it in my filter

Exactly as described and great price!

Este medio filtrante biológico es excelente tiene un buen tamaño incluso es más grande que el original que trae mi filtro de la misma marca

These work great in 2 of the marineland 350b. I take out the cartridges, add sponge, filter floss, these and filter floss. So much better than the cartridges

Very nice product!The one that came with my filter also came with a bag and you had to fill the bag, and everything. It never really was flat. Earlier this week I notice it was missing from my filter and the lid for my filter was ajar. After trying to think who did this I thought perhaps one of my 4 legged friends has a hand in it. After about an hour of searching and then about another 30 mins of searching later that day. I broke down and purchased this one. I'm very happy with it, however it was sent in one of those padded envelopes from amazon so in the process of getting her the box got squished. But the product was unharmed. I did eventually find the old one, it was downstairs and then about 150' after that, thanks to the cat.Attached are images of the squished box and the comparison between the styles (ignore the teeth marks)

Easy to use and keeps my tank clean.

I have a 55 gallon heavily planted tank that uses no carbon in the filter, just these pellets, as carbon in the filter would take out the nutrients in the water that I worked so hard to get in there in the first place!I have been using them for about three years now and haven't had a single issue. I place one of these in the canister filter where the carbon would go, keeping one in the bag and the other out of the bag (there are two bags in each box). Once every three months, I dump out the pellets that weren't in the bag, open the bag with the pellets and dump them in there and add a fresh bag of pellets which ensures that my beneficial bacteria stay alive and healthy.I've never had an issue with water chemistry using this product. If you use biological filtration exclusively, I would recommend this product without hesitation.