BRS two-part is definitely cheaper. The lab that I work at we get CaCl2 in bulk along with NaHCO3...so it costs nothing for me. With BRS, you're getting the same thing. It just requires some mixing and stuff. B-Ionic is premixed so I guess that's where the price difference is. Also if need be, what you can do is let the clam plant it's foot on a small flat rock...so if you need to move it in the future you can just move the rock with no harm to the foot.