Review on Marineland Cartridge Refill Penguin Filter by Kris Wagner

I used to sell filters for less than $1 but lately the price seems to have gone up. An internet search for homemade filters came across this gem and I ordered two. They have been in my aquarium for a few weeks now and I am very happy. Since I had a filler bag, I used it instead of buying sheets. This charcoal works pretty well, but it's not very rough and some of it will fall out of the holder. The holder is a bit fragile, please be careful when opening and closing. I change the filter material much more often. If you have an 8" Pleco, there's a lot of poop on the filter. I will order some spare parts to make the swap easier. I love these things!