Here's what we need to start: a Marineland Eclipse 1TL (we use the TL - twin light version because it has ample room for the bulbs. It might be possible to do a similar mod with the single light version, but we haven't tried it), an Advance REL-2P-32 ballast, two 28W Custom Sea Life compact fluorescent bulbs - one 6700K daylight and one 7100K blue, two compact fluorescent bulb clips, an Advance RS-22-32 ballast (or a Magnetek 449-LR-WS-TC-P, see step 1 below), and a power cord with a grounded plug.
Everything except the last two items is available here at Inland Reef Aquaria, the RS-22-32 ballast (or the Magnetek equivalent) and power cord can be found at Home Depot. While you're there get some small wire nuts, the right size ones are blue. You'll need about 10 of them.
Marineland does not condone or recommend this modification, and it will void their warranty.
Cut the plugs off both ends of the RS-22-32 ballast as close as possible to the ballast body. We'll be keeping the plugs and tossing the ballast. I know the good folks at Advance Transformer spent many hard hours building it, but it only costs about $14 and it's the most convenient source for the plugs. Besides, they probably cost more than $7 each if you could find a source. In case your local home improvement store carries Magnetek ballasts instead of Advance, then you need a Magnetek 449-LR-WS-TC-P. It has the same plugs and costs about the same.
Next cut the power pack off the Eclipse hood. This is the ballast that runs the original 18W bulbs that come with the Eclipse. We'll be re-using the three conductor wire that runs from the power pack to the lights. Discard the power pack.
To do the rest of the work, we'll need to remove the lighting unit from the rest of the Eclipse hood. One of the hinges has a small white nylon pin (pictured above). Pop this pin out and lighting unit can be removed.
Now you should have the lighting unit separated from the rest of the Eclipse hood. Take off the clear plastic cover by turning the white locking screws 1/4 turn and lifting the cover completely off. Remove the bulbs as well.
Next remove all six screws holding the white plastic panel to the black lid. Set the lid aside for now, all remaining work will be done on the white panel.
The original wiring should look something like this. We'll be getting rid of everything except the three conductor wire that enters at the top left. Clip two conductors of this wire off at the two sockets on the right side as close as possible to the sockets. The third conductor is much shorter and should be attached with a wire nut, remove this as well. Remove the original switch. The modified hood will have no switch - just plug it into a timer. Clip all of the other wires that connect to the original light sockets and remove the sockets by pushing them out from the other side. This will probably break the plastic tabs that hold the sockets, but we won't need them again.
The panel should now look like this:
Take the two plugs that you removed from the ballast and place them through the old socket slots. One on each side, one in the upper slot and one in the lower.
Connect the yellow wires on both plugs to the center conductor of the original three conductor wire. That's two yellow wires from each plug, so a total of four wires are attached to the center conductor. The two red wires attach to one of the remaining wires on the three conductor wire, and the two blue wires to the last wire.
Next cut two small slots about 1/2 inch long and 1/2 inch apart in the locations shown above. These will hold the bulb clips. We just drill a series of small holes to cut the slots - they don't have to be pretty. Work the clip through from the back (wiring) side. They should stay in place easily once you get them in.
Pop the bulbs into the clips. The clips may be a bit stiffer than normal since the slots they are in will keep them from flexing, so be careful with the bulbs here. Slide the bulbs as required to get the pins into the sockets.
O.K., time to re-assemble everything. Screw the white plastic panel back onto the lid - careful here, these screws just go into plastic posts so it's really easy to over-tighten and strip them. Also, make sure the three conductor wire and its strain relief are properly seated in their slot. It's a tight fit getting the clear plastic cover back in place, but it can be done! You remembered where you put the nylon hinge pin, right? Route the three conductor wire back where it was, there's a little routing diagram inside the filter chamber cover.
At the other end, connect the three conductor wire to the 2P-32 ballast. The red wire on the ballast goes to the center conductor, and each blue wire goes to one of the other two. Connect the black and white ballast wires to the power cord wire - black to black and white to white. The green wire on the power cord is the ground and should be attached with a screw to one of the mounting holes on the ballast.
This project uses a two bulb ballast so there is no way to turn the blue and white lights on separately. It is possible to use two single bulb ballasts, but then you can't use the original three conductor wire and the attached strain relief that seals the lighting section of the hood against moisture.
Since there is no power switch, get a grounded appliance timer to plug the ballast into. Set the timer for a normal day/night cycle - about 10-12 hours on.
We have successfully raised Green Tree Coral (Nephthea), Xenia, Ricordia, Zoanthid polyps, Seriatopora, Montipora and Acropora in a 10 gallon tank with this hood.
Important Note: All do-it-yourself projects are at your own risk. ReefTime.com and/or its employees will not be responsible for any damages caused by using any of the plans or projects posted here. Use reasonable care when dealing with electricity, especially near salt water! Plans involving electrical wiring may not meet local code requirements - When in doubt consult a qualified electrician.