i got my tank in.. i also got the Mega-flow kits that came with it....each kit came with one 1" bulkhead and 2 of the 3/4" bulkheads.. the hole in the 3/4" bulkheads are the same, but the outside diameter is different.. i have to order a few new bulkheads because i don't want the ones that came with it with the barb fittings.. i don't know which ones to get... can anyone help????