Modified MH/T5/LED Fixture with Hood

FaceOfDeceit · Oct 8, 2010

I had been trying to sell some extra lights I had for some time, with no bites. I also had a 30 Gal sitting around, some sand, and free time.

So instead of sitting, I decided to build a new tank.

This would be a 30 Gal (36x12x16), used to house small frags until I can get a proper light setup for my big tank (LEDs are expensive!)

I had a 2 x 150W MH Coralife fixture, and a 4 x 39W T5HO RetroKit with an IceCap 660 Ballast. Putting the MH and T5 (only 2 of the 4) over a 30 gallon would be WAY to much light given the depth of the tank. So, I decided to modify the MH setup, turning the 2 150Ws into a single, centered 150W.

I also had some CREE Royal Blue XR-E LEDs from RapidLED.com sitting around, and a driver (LPC-35-700W). After removing one set of MH, and all attachments inside (fan, relay...), I had plenty of room to covertly install the driver.

I then cut strips of Aluminum to utilize as heatsinks. I drilled and tapped the undercarriage of the fixture, and attached the strips, spacing them about 3/8" off of the fixture using strategically placed nuts.

I then left enough room with the top of the screw to wrap the wire to for a nice, clean look.

The original MH fixture had a fan placed in the center of the fixture, between the 2 MHs. I didn't like this idea, and since I had to move it anyway, to install a centered MH, I trashed it. I had 3 case fans laying around, and bought the necessary parts to install these on top of the fixture.

The "hood" is not really a hood. It is more of an open air front and back cover that does not rest on the tank, but rather on the MH fixture. I did this to help with cooling, oxygen transfer, and aesthetic look of the tank. I used 1/2" plywood, and cut strips. I set the MH fixture, using its legs on the tank, and got my measurements. I then cut my pieces, and figured out how I was going to install the T5HO equipment. They are set at an angle, to close the gap between the fixture and hood front and back. I also installed hinges to raise the front open, for easier access to the tank.

The whole setup can be lifted off by grabbing ahold of the MH fixture. The slats for the hood just rest upon the top of the fixture. The T5s are attached to the hood, not the MH fixture.

This is very simplistic, and serves its purpose. Not counting the lights themselves, this whole set-up cost me less than $40 to build. I got the T5 retro for $100, the LEDs for $40, and the MH fixture, came with my large tank setup, but break down to $200.

And as an added bonus, I have a single 150W MH "pendant" retrokit now.