Need to get crackin on DIY canopy!!

[thedocta]

Hey guys I sold my old lights and bought my new MH retrofits today so I need to get my plans down for my canopy so I can start building this weekend. And help would be appreciated! Thanks-Greg
Plan- 19" x 25" to fit on my 18.5" x 24.5" tank. Conatining 1 x 250 watt MH with 15000 k bulb. Ballast mounted to back, fan blowing in also on back. Light bulb 4-5 inches off water and canopy rest on the tank rim. Need to have a space cut out in the back for my HOB skimmer. It's a bakpak so I need 7-9 inches of space for that. Plan to eventully add phosban reactor so I need room for that also. Light colored wood to match tank trim. 2 doors that flip open on hinges on left side of canopy.
Questions- How much will this cost? How long will this take? How do I mount the retrofit? How do I build in a fan? Where do I get the fan and what size of fan? What type of finish should I use? Did I forget anything!?!?!

 

[kpatrick]

As far as the fan, you can pick up a 3 to 4 inch fan with a/c adaptor for less then $20 at most computer supply stores. They main thing you need to worry about is noise from the fan so dont get too large of a fan. I have (2) 3.5 inch fans with 31cfm and they keep my 125 cool and I have (3) 250 MH bulbs under the hood. My canopy is oak and it is 12 inches high. The back has a couple support beams that run from one side to the other for support but it also has a lot of open space for the hot air to escape. I used oak on my canopy but that can get kinda expensive depending on your budget. Hope this helped you out some.

 

[thedocta]

Yup this helps...how thick of wood should I use? I'll prolly try to do this cheap and still make it look go so I'll pick out whatever wood matches my stand color and is not to ruff. -Greg

 

[thedocta]

Need suggestions...tips...designs and plans!

 

[kpatrick]

I wouldnt use anything less then 1 inch. I used 1 inch on mine. I also added corner brackets on the inside to help hold it together better. The outside of mine is painted but I used polyurethane on the inside to waterproof it. On the corners I also used wood glue and a little caulk to make it look solid and to keep light from shining through the seems

 

[thedocta]

OK...should I use all wood glue caulk and clamps or should I use nails? 1"??? That seems pretty thick...I've been told on another site that as thin as 1/4" will do it. O well I'll check the prices and probably go with 1/2 - 3/4. -Greg

 

[msd2]

If I read correctly this is going on a 40 gallon tank and the mh is going 4 inches from the tank. My concern would be this could add a fair amount of heat to your tank. If your tank is acrylic its way to close to it, you need 12 inches. Finally, if your putting a reflector in the canopy make sure you put a small spacer between the wood top and the reflector, helps reduce the heat a lot.

 

[thedocta]

OK I'm now planning on about 12 inches between the water and the bulb...On another site I was told that any splashing water would crack the bulb if it hits it when it's hot so I'm goin with 12 inches. -Greg

 

[kpatrick]

Twelve inches is pretty safe. I think mine are 8 inches from water. Your reflector should come with little spacers to keep your reflector from touching your hood. You can use what ever you prefer to hold the canopy together but since mine was going on a 125 tank I wanted to make sure it was built well. I first used would glue to help hold the wood together plus it helped fill the cracks and keep the light from shining through. I then used my nail gun and shot some 1.5" nails into the corners as well. Then I used "L" shaped brackets to secure the corners just for better support and strength. You may not need to get carried away like I did.
Im afraid if you use 1/4" you may have issues with the heat from the MH light warping your wood. Keep in mind that 1" boards arent actually 1" but more like 3/4"