I have bee testing my alk weekly and it drops .5-1dkh per week. My calcium is 460-470 and mag is 1350(elos). Is arm media not good or should I be mixing the calcium media with something else?
If you are not getting enough output from your reactor just crank it up. More water flow in and out, more CO2 in. For a tank with a lot of fast growing corals, the alkalinity of the water you do small water changes from is really not very important. If you really think it's low, just add some sodium bicarbonate (baking soda) before you do a water change.
ARM works fine and you'd be very surprise how much calcium and alk output you can get from even a small calcium reactor.
Yes it will. You can try to match the waterchange water to your tank alk faor a couple weeks and see if it still drops over the coarse of a week and that will tell you if you need to increase the output of your reactor.If I crank up the reactor will my calcium(470) get even higher?