My thoughts and figuring is that 1 bag of rete is about 0.6 cu. ft of volume , and 0.6 cu ft of volume in a 4 inch pipe should be about 5-6foot long, so if I take a 10 ft piece of pipe, fill it with 2 bags of crete (160 lb) I should be able to make a circle about 3 ft across. On that I should be able to fit 8-10 stalks of boo on it, then just slide the whole dern thing off the front of the boat using a couple of 2x4's.