DIY 29g Halide Hood

[Subliminal]

Hey guys,

I recently decided to give halides a shot, and got such a good deal on a ballast that I'm going to build a hood.

But...I have some questions.

First I'll outline my (tentative plans)

I'm planing on making the thing out of wood. I have some pine left over from my entertainment stand project that I think will work quite nicely...so I'm going to use that.

I'm going to use a 175 single ended setup with a 14k bulb, and probably some form of parabolic reflector. I like the idea of a small pendant hanging from the ceiling, but i'm worried about it spilling light into the room...my wife would be upset, and there's no need for that.

So, say I make the traditional tilt on the back side, walls and a lid.

I'm thinking of putting the bulb 6ish inches from the water.., but not sure if that'd be optimal. I want to keep the heat away from the water, but it does need to penetrate to the bottom.

I plan on mounting the reflector to the inside of the lid, probably about in the middle, with the socket in the back (reflector spread out sideways, rather than socket sideways).

I plan on hinging the lid, but have to figure out the best way with stuff hanging on the back of the tank.

For a vapor shield (which I assume I need over an open tank), probably a sheet of acrylic/plexi from home depot...not sure if this is the best, or how far away from the bulb to put it.

Somehow rig a few fans (or would cooling slots be enough?)

Any advice about heat control, distances between materials, etc would be greatly appreciated.

Definitely in the drafting stage.

Thanks!

damon

 

[concept3]

6 inches is a little close to the water. It will heat up too fast, try about 9 inches so airflow is optimal across the water's surface.

Slots will not be enough, you will want to put computer fans or something to facilitate warm air draw.

Vapor shield will not be needed as you are using an SE bulb, BUT if you want to cut down on salt spray, it is a good idea. However, it will keep the temp high. Evaporating water cools down the tank plus you have to keep it clean a lot! Acrylic/plexi will warp and crack over time. They don't like the UV coming from our reef bulbs. Glass is best.

Hinging the hood will definitely allow access. I have mine hinged at an angle for ease. My hood (and I've made smaller versions for a few friends)sits on top of the tank with the back wide open so you will not need to hang it.

The light spilling out the back of the hood? If you mount the parabolic reflector sideways (socket to the left or right, not back), most of the light will be redirected down to where you need it- the tank. Most lights cover about a 2' X 2' area anywhoos



-sorry, it's in no particular order, fingers just kept going

 

[Subliminal]

Thanks for the reply.

My replies...also in no particular order:

I was thinking the reflector turned in the direction I first mentioned to better dispurse the light over the 30 inch wide tank. Which way gets the best dispersion: the sides of the relector or the front/back of the bulb? My guess was the sides, but I don't know...I could be wrong. I plan to use a parabolic reflector, unless there's a reason not too. I also have the aquafuge hanging on the back, so light spilling into that is certainly not a problem.

9 inches from the bottom of the bulb or the top? Grasping at straws a bit, but figured that'd be a worthy question. My current light has a plexi reflector on the bottom, which is about 3 inches from the water surface and almost never gets dirty, so it WOULD be nice to not have to use a vapor barrier, if I can avoid it.

Computer fans are no problem. I have 12v converters (from old electronics equip.) and plenty of cpu fans laying around. I'm thinking I'd like to use 120+mm fans on dials so I can control the speed/noise. Much like I do on my homemade computers.

Thanks for the replies. It really helps to hash out this sort of thing before just diving into the project.

 

[Subliminal]

Ok, just ordered the rest of the stuff from premium aquatics:

14k-175h 14k 175watt Hamilton Halide Bulb - mogule 1 $64.95 $64.95
REEF-LECTOR12 PFO 12" Optimal Perpendicular Reflector Only 1 $22.00 $22.00
LN-MOGULE Mogule Halide socket and bracket 1 $ 9.95 $ 9.95


So, $150 total for the 175w setup. Not too bad, and I hope I ordered the right stuff!

 

[mladencovic]

...
and probably some form of parabolic reflector.
...

Strictly speaking you don't need parabolic reflector. Any reflective surface shielding the back and partially the sides of the bulb will be sufficient. On the other hand, if you are more concerned with some easthetic visual effects and want to play with the tight focused beams of light higlighting small areas of the tank, then yes, use parabolics. 8)

 

[MikeNapoli]

Damon,

I know this DIY is done so i think it's about time you posted some pics.

 

[Subliminal]

There ya go. Not the best pics, but they're what I've got!