Well the wife does not want to deal with the kalk while I travel for work and my tank needs the Ca/Alk boost now as the corals are blowing up. So, I'm going to install a CO2 Ca system. Anyone have any experence with this regulator/solenoid. good, bad, fine tuneing? Should I get the extra needle valve for $32ish to fine tune? Going to order tonight if i get some feed back. http://www.fosterandsmithaquatics.com/product/prod_display.cfm?pcatid=9895 TYIA