From what I heard when you buy boxed
LR online and its rated at 50lbs, its 50lbs with the cardboard, wet newspaper and all, so its actually much less in actual
live rock (i dunno mayber 40ish lbs...maybe someone can pipe in with experience). Plus when you add in shippnig that 3.99/lb
LR is now about $7
I'd check out a reputible dealer in the area and get it there, taht way if you want 10lbs, you get 10 lbs...plus many will lower the cost the more you buy.