ive owned a rkl and now own a rk elite, love how simple they are. programing the reef keeper's is very simple, took me about hour to mount and program my setup and i have 3x pc4, sl1, and sl2, also run my ato off it, monitor ph, orp, salinity. if your going to get a bigger tank with more gadgets plan ahead and get a rke, the rkl is nice but you can only plug in a total of 4 modules.