it would work fine cinder blocks can hold ALOT of weight just make sure you have somethin flat on top of them to put the tank on
Or have the tank resting on the trim don't have it resting on the glass right under the tank like my brilliant science teacher did great way to crack a tank
If i get a tank with out a stand then i'm thinking of putting it on cinder blocks i like the kind that have groves that fit to geather like a puzzle that way it has even less of a chance of shifting around or haveing a cinder block kicked out but wih the weight of a large tank on top of them i don't think they will move eazily
