if you have the space, they're awesome. I had a 17g one in my system, and when I'm done with the new one, I will have a whole 40g breeder for it.
Pods, sponges, feather dusters and all kinds of other cool stuff grow in it, and since mine was also PACKED with LR, it also acted as a nitrate sponge.
very cool part to add to your reef.
