DIY aluminum light hood ====> circadian rhythm

[proaudio55]

Here's a DIY project of mine. It's a hood that emulates the progression of the day. I don't know if fish/ plants are sensitive about their circadian rhythm, but I know I wouldn't want to wake up by going from darkness to full-blast grow lights in a split second .... then go to instant darkness at the end of the day. So I set up a system that ramps up the light and ramps it back down.

The brain of the system is 3 off-the-shelf timers that are wired in like wall switches. To elegantly house them, I milled an electrical enclosure so I don't need a snarl of power strips and cords. That box sits on the floor, out of the way. I also included a 10 amp breaker so I don't burn the house down. Most recently I rewired it so that it runs with just 1 multi-conductor cord and industrial multi-pole plugs.

The hood is something I fabricated out of 0.065" aluminum. It's a 'trough' 35.75" long, 4.5" deep, and 8.25" wide with end caps TIG welded on. The light sockets are just porcelain 'lamp repair kits' that you can get at any hardware store.

The way its programmed is:
Light 1 ~ 8AM-10PM ~ 1.1w LED night light
Light 2 ~ 9AM-9PM ~ pair 26w 2700k CFL
Light 3 ~ 10AM-8PM ~ Four 26w 6500k CFL

Plants are . . .?? Whatever can put up with my neglect
Tank is a 46 gallon bow front, 20# CO2 bottle, Cascade 700 filter, tiger barbs, lemon tetras, flying foxes, glofish

Pic 1: Overall look
Pic 2: Control box
Pic 3: 1.1w LED
Pic 4: 1.1w LED + 52w 2700K CFL
Pic 5: 1.1w LED + 52w 2700K CFL + 104w 6500K CFL

[proaudio55]

The timers I used are off amazon: Aube by Honeywell TI033/U 7-Day Programmable Timer Switch, White

And this is what it looks like inside / backside, before I did the rewire.

The fixture is wired
2 - 3 - 3 - 1 - 3 - 3 - 2
Chanel 1: LED
Chanel 2: 2700K
Chanel 3: 6500K


I went with standard bulb sockets because this is universal and VERY easy to upgrade / play with. It takes seconds to change bulb wattage, color temperature, etc. CFL's are inexpensive now and it's only a few bucks every 6 months to swap them all out. In the future LED grow lights will come down in price (and go up in performance); I guarantee those will be compatible with this fixture too.

Pic 1: the underside before I rewired it to a single multi-conductor cord.
Pic 2: The style plugs I now use
Pic 3: The style plugs I now use

I'm not really looking for any input, I know this is dumb and way overkill . . . I had fun, even if this is more appropriate for a reef tank or something. I'm getting great results and I hope this idea can help somebody.

Best of luck to ya'll!

[sayurasem]

Man I need to take some electricity classes first before I can a temp this!

[Naekuh]

Originally Posted by sayurasem

Man I need to take some electricity classes first before I can a temp this!

lol actually you dont... you can just study how to wire circuits.

If you look at his setups, he's using the E27 CF's, which have there own internal balasts, there isnt much mixing voltages in his setup, so its a straight wire job.
The LED's are probably on there own circuit seeing how there is a timer for them as well, so he's keeping same voltages to each circuit.

Its just a matter of wiring up the proper 120V/240V circuits.

It gets complicated when you need different voltages... thats when you want to take a electrical class and learn how to build transformers. :P

[jdm68]

It's funny, but I have always thought that going from

Originally Posted by proaudio55

darkness to full-blast grow lights in a split second .... then go to instant darkness at the end of the day.

would be stressful for fish as well. I know I've seen them "jump" when the lights go out.
This is a really cool way to try and mimic the "real" way that light works in nature. Now you just need a moonlight on a 4th timer, and then a 5th circuit for an intermittent storm/cloud system for that super real effect! You could have it dim and then have super bright flashes of "lightning," maybe even add in a way to make it rain...
Just playing, I think this is really cool, good work.

[proaudio55]

Originally Posted by Naekuh

lol actually you dont... you can just study how to wire circuits.

If you look at his setups, he's using the E27 CF's, which have there own internal balasts, there isnt much mixing voltages in his setup, so its a straight wire job.
The LED's are probably on there own circuit seeing how there is a timer for them as well, so he's keeping same voltages to each circuit.

Its just a matter of wiring up the proper 120V/240V circuits.

It gets complicated when you need different voltages... thats when you want to take a electrical class and learn how to build transformers. :P

Yep, you've got it exactly right, the LED is a 120v screw in type. It's something you can pick up at walmart for a couple bucks that replaces a standard light bulb. This is a really simple wiring job, everything is 120v and about as simple as you can get (no transformers, no low voltage wiring, no resistors, etc).

[VA2GXB]

LOVE it. Doing practically the same thing here, except with LED bulbs (60W equivalent, I work for a 'certain' large company that makes these ) Glad to hear the tape is reflective...I did just that.