I got the calib solutions from here. I also use non-Apex brand probe, but its working fine. I used different solution i got from eBay before and gave me wacky reading. Turned out it was bad calib solutions. Might not be the case, but worth checking. Ok, about your LED plan, I hope its not too late, but 6 reds, deep reds and greens are way too many. I recently went broader with my LED, used only two (deep) reds and i think its perfect amount. I do have Neutral whites, but its far from being too "warm". Just in case, heres my rebuild thread. I really think this build should be moved to Show off your tank section.