I have a 250w lumenbrite pendant over my 21 inch cube'ish tank. The pendant is an octogon that is 16x16 inches. It has an unknown bulb that produces light similar to phoenix 14k. I'd like to add some actinic supplement to get a little more pop, but am still confused by the led ratings, etc. What led combination would be equivalent to two 24 inch actinic t5's? I'm considering the 18 led rapidled dimmable actinic supplement kit with 12 rb and 6 uv. This kit comes with two drivers and I would run 12 rb on one driver and the uv on the other driver so I can adjust the color as needed and for sunset/sunrise as well. Next question is how to mount the leds and in what fashion to the pendant. Either 1 row of 9 leds on two sides or 1 row of 6 on two opposite sides and 1 row of 3 on the two other sides. Figure the leds come with 90 spread and by tilting the rows inwards, there will be enough overlap for the entire tank. Is this a safe assumption? Two rows of 9 is easier but will the spread/coverage be satisfactory or is the 4 sided that much better? Thanks in advance.