VHO bulb dimensions

[tfreitas]

Hi folks,
I'm building a fixture for a 48" tank. Plan on using 46.5" URI bulbs. I don't want the fixture to overhang on the tank sides so I need the bulbs w/ end caps (German 3 piece) to fit inside of 47" (using 1/2" walnut). Is the 46.5" length of the bulb only or does that include the end cap? Bottom line is can I get a 46.5" bulb inside a 47" fixture?
Thanks very much.
Tim

 

[Entropy]

It will be very very very close. The 46.5 is from pin to pin, and the endcaps add about 3/4 of an inch unless you jam them on there really good in which case it is a PITA to swap bulbs. If possible I would make the ends stick out a tiny bit and make the inside of the canopy 47.5 inches. That should only stick out 1/4 inch per side if that.

By the way...

[welcome]

 

[stonecold]

I used to have a 48" tank with the same setup.....It will fit, but its gonna be very tight. You'll have a little bit more room if it overhangs on your tank rim.

 

[Entropy]

You can also router the bottom of your canopy so it looks finish and snugs up agains the tank really well. This gives the illusion of it being flush.

 

[tfreitas]

Thanks. Considering 36" bulbs and making the fixture 42" to give me plenty of room. Will that make the sides of the tank dark or will that be sufficient light - 4 x 95W/36" vs. 4 x 110W/46.5". Plenty of wattage I think, but no direct lighting on sides of tank.

Also, any suggestions on where to mount fan(s). Side of fixture with back open vs. fan in back. 1 or 2 fans? Looking at Icecap variable speed.

Do you need internal reflectors on URI bulbs if you have an external reflector in fixture? I've heard you actually lose lumens with the internal reflector.

Are the Moon LEDs worth the trouble or just a marketing thing?

Thanks again.

 

[Deleted member 82742]

Tagging along on this. Do the end caps add 3/4 each or is it 3/4 total. Is a 46 1/2 with end caps 48 inches or 47 1/4?

 

[david8956]

FYI - I run "46.5"" URI VHO's in my canopy. Just measured them, overall length including the waterproof VHO endcaps is exactly 46.5". Bulb itself can't be 46.5" long, but I'm not taking mine apart just to measure them.

Edit: My canopy is also 47 1/8" wide where these VHO's are mounted. Only a little over 1/4" clearance on each end.

 

[Deleted member 82742]

Thanks David, anyone else have any input?