I asked a similar question some time back but I had a total tank crash do to ATO while on vacation. Now, I am upgrading to a 180 gallon tall tank. 72 “long, 18” front to back and 31” tall. I bought four 48” T5’s and one Kessil AP700. I plan on stocking the tank with SPS alone with a wide mix of other corals. I plan to put the T5’s in the middle (left to right), about 10” high with two close together in the front and two in the back. (no reflectors) While my budget could allow for two units, I plan to move the LED fixture left and right to simulate the motion of the sun …mostly for the fun and visual interest throughout the viewing night. I would condense the solar day to 4 to 8 hours while running the T5’s longer as needed. 20 years ago, I built a moving fixture for two 250 watt metal halides. Now I can use an Arduino microcontroller and a stepper motor. Finally, I have two cheap pairs of 50 watt LED COB chipset from Sweden via China. One pair is 420nm and the others are 455nm. I thought about packaging them with no lensing or reflectors, in a straight line, evenly spaced with the 420’s to the outside. I would put them as low and as close to the front edge of the tank as possible. Maybe the low angle will add some drama to the tank but that remains to be seen. I will test them with a Seneye aquarium spectral analyzer (not the best but…) to see if the cheap chips are close to being right and to see how powerful they are. Perhaps I coulda gone in another direction all together. Of course you wouldna bought what I did …but… Being that I have this stuff, what tweaks and improvements would you make to this hair brained scheme? Is 100 watts of 420 and another of 455 too much? Would you just throw them in the trash?