I have a 220 tank with your typical dimesion for that of basically 30" high by 72" long. I have a maxspect 320 watt razor light on glass tops over it..it has two channels..I think its 15k..not the newest model but a couple of years old as far as the model year...I am trying to have a mixed reef tank with a couple of soft corals and some lps..maybe a couple of sps..I dont have a par meter...( i know i can rent one maybe) ..but what is the typical amount needed for a mixed reef this dimension..with no real need for sps dominant lighting...I have this razor running about 9 hours with some ramp up to around 95 percent for maybe two hours and then a very slow ramp down with heavier blues..mostly actinic around 5-6 pm..on at 10 am ..high point is like 1-3pm..then the slower ramp down..does anybody have a good educated guess if im at the right minimum amount ..or am I vastly under watts for those dimensions...

