DIY canopy... When PC goes bad...

[Rikko]

Well, thought I'd post this here as well as on my nano contest thread on reefs.org since I think it's fairly interesting...

The tank is an 8 gallon tempered glass cube:

The light you see in front of it is a 125W Terra Gro compact fluorescent bulb from the same folks that supply those self-ballasted T5 units in town. It's a full spectrum 6400K bulb. My rep says he sells them mostly to film companies to use for night shoots.



I built a box out of polycarbonate and put in 2 sloping pieces for help with reflection. There's no science in how they are in there - while I could have spent some time playing with sizes to get the optimal light returns, I'm far too lazy. The lump in front of the box is where the mogul socket for the bulb fits. It's a commerical mogul so substantially wider than your typical desk lamp kind of mogul. Because of the substantial weight of the bulb and even the socket, I wanted to make sure the canopy would be able to support it. To that end, I cemented 4 pieces of 1/4" polycarbonate together with a hole that very tightly accepts the socket. With 1" of material holding it in place, I think it'll be good for a few years.


The other end of the canopy. I cut a hole for a PC fan to help cool this bad boy, and later drilled several 3/8" holes in the other end where the socket is to let the heated air exit.



Inside view as the project was winding up. I used mirror tile for my reflector and siliconed it to the polycarbonate. With little heat I don't expect there's any reason the mirror will let go. Note the splices - the tiles are 12"X12"... My canopy is larger. Doh.


I also wanted some supplemental lighting in case the light wasn't blue enough for me. To that end, I got 10 ultra bright LEDs (6 blue, 4 UV) and made this little rig out of polycarbonate. It functions as a moonlight in effect.



And there's the finished project. The LED array is cemented to the side of the canopy and more mirror silicones around it to add to the reflection back into the tank. I'm really happy with it.. It's extremely solid and visually much more appealing than anything else I've ever built (should I be admitting that??). To boot, after 10 hours on, the light bulb is barely warm to the touch - I may even step the fan down a little bit if evaporation becomes a side effect.
Sadly, the LEDs aren't noticeable at all with the main light on. That's ok though, I like moonlights anyways.



Tank has been running all of two hours at that point. I'll update this thread from time to time and let everybody know what corals fared well under that. It's horribly bright in the room.. I had my overhead fluorescents in the room on and the photo makes it look like a dark room.

[BCOrchidGuy]

Hey that's a cool idea, I tried one of those for my orchid room and I found they didn't give off enough light for the area I wanted but it did get darned hot. How does it look now? anything growing in the tank? You'd notice alot more light reflected back if you got rid of the black/white aragonite and went with straight aragonite. I had a 15 gallon with the black/white and it just looked so anemic (light wise) I ended up with way more light (PC) and it still wasn't good. I traded the gravel for regular sugar grade and it was a huge difference.

Doug

PS what did they charge you for the lamp? when I bought mine it was about $90

[christyf5]

Pretty slick, nice work Rikko!

[BCOrchidGuy]

Yeah that would solve a bit of a problem with my corner tank where all the light is at the front.

Doug

[Rikko]

So far I'm pretty happy w/ it.. As I said in another thread, I really wanted to get my hands on a PAR meter to see what I'm actually getting off it, but they're a little pricey for such a goofy little experiment... Guess I'll have to do without.

The sand itself is actually an experiment, else I probably would have used white aragonite (or even BB) - that said, I do enjoy the contrast.

The diatoms have stopped.. Hurrah. Now it's clear and I *think* that some of the corraline that came on the rock is spreading a bit and I've got lots of mermaid cup algae sprouting off the rock.

The lamp itself is supposed to retail at around that price, I got it a little better because I manage the store (and the rep was also feeling generous that day).

Heat is not an issue with the bulb and fan, I'm happy to say. The PC fan runs at around 13V, so it's a little noisy, but I'm not so put out as to throttle it back just yet. The end of the bulb is cool to touch, and when you get to the base of it it's quite uncomfortable but still nothing too worrisome.

One constant complaint I hear about these bulbs is that the "spectrum is wrong and only grow hair algae". I certainly had a long hair algae bloom in my 65 (it just up and died last week, hoorah), but I dislike any argument about "spectrums" when the person making the claim can't be any more specific than that.

I'll post a few pics as the tank matures and we'll see what comes of it, I guess.

[BCOrchidGuy]

Cool thanks for the update, um what's the expected life span of that unit? Do they estimate a replacement period? Hydroponics shops sell them as well.

Doug

[Rikko]

I wasn't able to find any sort of expected life.. I'm sure they'd say 10,000 hours, but those compact fluoros seem to have a high failure rate. These ones are "better" than the garden variety ones, however, so maybe they're a little more sturdy. I guess time will tell.

AFAIK these guys are like 98% hydroponics and 2% aquarium - our rep is more of an experiment to see if he can open up a new market for them. So far I've been reasonably happy with their T5s and now these... If only they did high Kelvin halides too
Or should I say, if only I needed to grow tomatos?