I think these are great because all you have to do is buy carbon for them which is much cheaper then buying the whole filter cartridges all the time.

Pros: Cheaper then always buying new filters

Cons: No filter floss to purify the water.

This product saves so much time and money. All that is needed after the initial purchase is carbon. This filter keeps our tank clean for a bit longer then other filters we have used. Easy to use and no fumbling and having a mess like others.

Pros: Favorite for many using

Cons: never enough

these are worth the extra work of cleaning out and refilling the filer media as the save money and create less waste. You can also use biomedia and other types of filtering agents in these as well as carobon filtering.

Pros: great cartridge

Cons: not as easy to use as the replaceable

This filter is amazing! We were having trouble with our more expensive filter for our aquarium and the guy at the pet store recommended this one. We tried it and it cleared within 2 days! The tank is now beautiful!

Pros: CHEAPER!

Cons: none

they are easy to replace and quick I use these in my little tand and my fish Ive had a little over a year noe has never been sick so they do a good job

Pros: easy to replace

Cons: none