You'll love kessil if you like shimmer. That low (lol) I wouldn't use a reflector. The 500x is made for very deep tanks and acropora and just so its not a Hotspot I'd just keep the reflectors off....and this happened... they will go nicely with my 4ft T5 and 3ft t5 AqL fixtures. I plan to set them on the 75g to start coral acclimation. I plan to mount my lights 20"+ off the water so the a500x should work great. I'm excited to try out Kessil. Currently I run xr15 pros in my 75g.