I think the Koralia's are the way to go also. I bought the Marineland Maxi-Jets, and while they are a good value and seem to be working alright, the only problem is that the suction cups don't stay on the glass too well, you have to push them on every few days and worry about them falling off and making a sand storm (several people on this forum have had this happen). I think the Koralia is the only one with the magnet suction cup that never comes off. I bought a small one for my 20gal and it works great.