ok to many people to quote here...So i started my 1st SPS dominante tank in 2005 and have NEVER had an issue with my CA reactor. Since 2005 i have had to replace the impeller in the pump on the reactor ONE time cause i wore out the shaft in the tunze pump ($15) other than that i buy a bucket of ARM coarse Media once a year and buy NEO MAG for the reactor. This is ONLY my opinion cause this is the only thing i have used but to me its a NO brainer. I havent even recalibrated my PH probe in 2 years and havent purchased a new one since i bought the 1st one in 2005. Remember the theory of buy the CORRECT/BEST item the 1st time. When i started my 1st CA reactor YES i spent alot of money up front (but a SPS dominant tank REQUIRES it) if cost is and issue dose manually for a few months till you get the $ saved up and buy ONCE. As far as "How CA,ALK, & MG work in correlation"? Here is the simple and easy thing to understand it. CA and ALK are a direct correlation of each other but without MG neither one will work. MG is the binding agent for the 2, no matter how much CA you add to raise the CA level it wont do a thing unless you add MG. I have(a very long time ago put 4oz of CA in the tank at one time and all it did was settle). That being said, thats why i put NEOMAG in my CA reactor. I now dont have to dose anything. My CA stays at 460 My ALK stays at 11 and My MG stays around 1400. 24/7 365 days a year. I NEVER EVER even check the levels anymore. All i look at is the PH of the tank on the controller and i can tell you what all 3 of those levels are. Also there are MANY things a dosing pump cant dose that is naturally dosed with a CA reactor normally. If you melting coral skeleton, and media you are putting back what the corals and all needs. REMEMBER i and no professional. These are JMOs over the last years. But i did stay at a Holiday Inn Express last night, JK. If you would like help feel free to PM me. Sorry to ramble