I would imagine we're all trying to keep the costs down if and where we can
I have used both a reactor and dosing pump. Personally I like the dosing pump as its easier to maintain my chemicals (used to have to take my co2 tank in fairly often and the shops hours were pretty restrictive, same hours I work) and I think the dosing pump keeps my parameters much more stable. You may want to invest in a better reactor? I don't know how great the coralife ones are (I've seen their skimmers in action and I wasn't impressed by them). My first calcium reactor was great, no problems and I filled the co2 tank every 9 months or so like clockwork, then I decided to "upgrade" to a fancier reactor and I had nothing but problems which made me want to switch to dosing. I do find dosing to be more expensive so far but not expensive enough to make me switch back to a reactor.