Trouble is, getting someone to take 20 lbs out of a system would screw up their system. You don't have to get it from me, I really don't care, but if you get 3 cups from 3 established systems, 1. you'll get better diversity, and 2. you'll have plenty of organisms to seed the sand. You'll also get pods and mini stars from live rock when you add that, and also some bristle worms.