I had been toying around with going with LED lighting for this tank, after looking at what's available and what it would take to DIY, I decide to wait a while (not in the budget atm). The problem that I have with my current set up is that the tank is 72in long, and my lights are 60in long. This leaves some noticeable shady area on the ends of the tank.
I had some 48in CoralLife quad fixtures laying around, and had some new bulbs so I decided to adapt them to my setup. Since the tank is only 18in deep on the sides, I will have a little overlap since the lights are 21in. I plan on putting on a background sometime in the future before i flood it, so the overlap will not be too noticeable.
My first step was to cut the lights down to size. I took them all apart, stripped out the wiring and ballasts, and cut the reflectors in half. The lights come apart into two pieces, one for the bulb area and one for the wiring and electrical. I used just the bulb frame and cut this half as well.
To mount all this, I bought some 1/2in aluminum channel, some 10/24 threaded rods, nuts and washers from lowes. I used the channel to make the frame for the setup and drilled it so that I could use the hanging kit to attach the rails between the lights. The rest is self explaining in the pictures.
I did not wire in the fans from the fixtures, the ballasts are mounted on pieces of channel that act as heat sinks.
Each side is able to use 2 bulbs, but that was too much light (130 watts/side), so I'm only using 1 atm per side.
The bulbs are dual daylight\flora or 10K\6.5K in color. I also got some new bulbs for the main lights that I will put into play when I flood the tank. I was not really happy with the bulbs that came with the original fixtures (Aqualine plantgrow)they looked too pinkish, so this time I went with a combo of Geisemann midday and aquaflora powerchrome bulbs.
The addition of these lights really brightened up the ends of the tank. I will need to adjust them when I flood the tank to get the correct par settings.