I am very new to calcium reactors, Krolin 1502, and controller, reefkeeper lite, just monitoring ph until I can find more parts. Got a hand me down reactor with new media but am trying to prepare for top off/changing media. I am unsure what is in reactor right now but I think it is ARM coarse. I was searching and on Amazon I found Middle Keys Marine Life media. I was wondering if anyone has used it and good results or what others are recommending.