I am currently running 2 Red Sea RL50s on my 36 inch tank they are doing a great job giving off enough par to my sps that are 8ish inches below the top of the tank and more then enough par for my Zoas softies and lps corals closer to the bottom or on the sand. I was just wondering when I upgrade to a 4 ft tank do you think a 39 or 48 inch ai blade to supplement the RL 50s will be enough to keep up the success?