I use an algea magnet called a mad-float I believe. Some magnets lose the connection easily and will sink to the bottom and when you get them back together the one at the bottom of the tank picks up substrate and sctratches the crap out of yuor tank. That is what is unique about the mad loat if it loses conection(which it very rarely does) the one inside floats to the top. this is also helpful in getting it out and putting it in.
I find the algea magnets far more convienent and effective on the glass.
I've also heard that the "twister" is a good magnet.
------------------
Clint
CDevoe1111@aol.com