LOL I never clicked the link. I thought you were talking about the neomag from two little fishies. Its a small magnet for nano tanks, which is apparently called a NANOmag.
*sigh* I really gotta get more sleep.
As for the brightwell aquatics NEOmag, no I haven't tried it but I assume its the same type of product as the zeovit or ultralith magnesium granules that go in your calcium reactor (it even has the same ratio of calcium media to magnesium media). I have used the zeovit brand one in my calcium reactor and they worked awesomely, my mg levels were spot on all the time. I only stopped using them because I switched from a reactor to a dosing pump.
Ok I'm off to confuse people in another thread now