I use them on my breeding systems because I have to feed a LOT. I change them every 2-3 days. I usually take them outside and clean them with the garden hose until it gets too cold. During the winter I do it in the laundry tub.

I use the large ones, 6" diameter I think, so I don't have a problem with them getting fully clogged but I do keep an eye on them.

I don't use them on my reef tanks.