Penguin Filter Cartridge B

These things last forever! It say to change it every week or two but I do it about twice a year :-) They are pretty cheap, too. They are about $4 at PetCo, so I am sure they are cheaper elsewhere!

Pros: last long cheap

Cons: none

Once I tried the Penguin filters, I stayed with them as long as I had my 30 gallon tank (about three years). The filters are relatively easy to use, although installation can be delayed a little when the outer edges don't properly align for placement. Excess food and fish waste accumulate on the filter and can be rinsed off occasionally to extend the filter's life. The filters are on the expensive side, but they do a good job and the added expense is a good investment.

Pros: Holds the "gunk" and lasts fairly long

Cons: Can be a little difficult to align/edges get caught