Retrofitting Eclipse 2 Hood With 55w PC

Adam T
  • #1
I'm attempting this project this weekend. From what I hear, some have had trouble with excessive heat, while others have had problems because the retrofit fixtures have nothing to protect them from water. Aside from being a touch unsafe, the very reflector gets grungy and doesn't do its job as well. So......since I like the look and function of the Eclipse, and I don't want to buy all new filtration equipment, hood, etc., just to upgrade my lights, I am fabricating a vented enclosure out of plexiglass.

If anyone has done this kind of retrofit before, I'd sure appreciate any tips you can pass along.

  • #2
Haven't done it, and don't have the tank but you can buy a small computer fan to keep it cool and maybe put a glass canopy on.
Adam T
  • Thread Starter
  • #3
I actually really like fabricating stuff, so I'm looking forward to this.

I plan to use 1/8 acrylic for the base that will attach to the Eclipse hood. This will serve to insulate the hood from the direct heat of the lamp. Cooling slots will be milled into the base at the center, and a series of holes will
be drilled through the Eclipse ABS canopy above the cooling slots in the base, which should minimize the collection of heat under the hood.

I'll be making a wood jig in the shape of the lens, and form a piece of pre-cut 1/16 acrylic sheet to it by placing it in my oven at the temp and for the time specified by the mfr. This will produce a one piece lens, which will be edge glued to the base.

The end caps of the acrylic enclosure will not seal the enclosure, but rather, will have slots at the bottom which will serve as inlets for cooling air. This should produce a convection airflow path from the bottom ends to the top center of the enclosure, and then out of the hood.

The main thing I am worried about is that I'll have to relieve a couple of molded cross braces in the ABS hood to provide clearance for the new fixture. I have a plan to reinforce it, but this will be the tough part I think.

Should be a fun little mod. If anyone is interested, I'll post pics of the fabrication process and the final completed project.
  • #4
Adam T
  • Thread Starter
  • #5
Well, I completed the retrofit this weekend, and I thought I would share the results. I fabricated a vented enclosure for the new fixture out of clear acrylic. I used 1/16” sheet for the lens and 1/8” sheet for the mounting plate and the sides of the enclosure. Here is the finished result:



This tank is BLARING with light now:


In addition to the increase in wattage, the new reflector is MUCH more efficient than the stock setup, and it is obvious that a lot more of the light is getting into the tank. It seems to be more than twice as bright as stock, even though I only went from 30 to 55 watts.

I know that these lights will generate more heat than the stock setup, so I provided for good ventilation that should create a nice convective flow through the enclosure from top to bottom:


Since I have an acrylic tank with a center brace, I noticed that the center portion of the stock light enclosure was always perfectly clean. It doesn’t get splashed or dirty because it is protected by the center brace. Accordingly, I drilled my vent holes in the lens in the center, where it won’t get splashed or dirty.

The stock setup just vented into the interior of the hood. I decided it would be better to vent the enclosure directly out of the hood, so I drilled 1” holes through the Eclipse top and installed the snap-on vent covers supplied with the AHS retro kit:



Also, I know that acrylic tends to expand a lot with heat, so I secured the new enclosure to the Eclipse hood using the existing mounting lugs, but I drilled my holes oversize and used silicone tubing to act as grommets that will allow for the expansion and contraction.


I used the same method to attach the reflector to the mounting plate using 4-40 machine screws and nuts (don’t try to thread into the acrylic – it won’t work well).

Space is very tight (you simply could not shove any more light into this hood), so I routed the cord straight through the reflector and then out a slot in the lens. (I didn’t clean up all my shavings before taking the pics, so it looks much better cleaned up).



Note the screw through the Eclipse bulkhead at the left. This screw secures the lens in place. There is another one on the opposite side. The lens can be removed to change the bulb by simply removing these two screws.

The cool thing is that this is a direct replacement for the stock unit. It simply screws on with the original six screws that secured the stock unit. I could drop the stock unit back in without any problem at all. No modifications of the hood were necessary except that I had to tack glue spacers onto the lugs with superglue gel.


I really enjoyed the project and I am very pleased with the results. I actually think it runs cooler than the stock setup due to the direct venting. If anyone wants to attempt this project themselves, let me know and I’ll be happy to answer more detailed questions. If you don’t have a table saw or some other way to accurately cut the acrylic, this will be pretty tough for you. On the other hand, if you have the tools and are at least moderately handy, this project should be no problem for you. I would say that this project is moderately difficult overall because you have to fabricate the entire thing based upon trial fitting and your own measurements, without the benefit of specs. If you are interested, you could probably benefit a great deal from my measurements.

Hope someone finds this helpful. Time for a beer and a nice cigar. Cheers.

Top Bottom