DIY LED trial run

[wontonflip]

OK...fixed the video:

[ame=http://www.youtube.com/watch?v=2KM062tSsSE]YouTube - DIY P7 LED Test[/ame]

 

[PRC]

Nice thread Wonton. I can't really tell form the video, are you getting a spotlight effect into the tank?

 

[wontonflip]

Not really.....you have to remember, this is just ONE LED, running off 2 AAs. Once hooked up to a real power supply AND once there are more LEDs, it would just be super bright.


EDIT: Plus we will put reflectors onto the unit to direct the light into the tank.

 

[PRC]

That's great. Let me know how it works for you, make sur eyou keep posting on this thread. I know everybody is interested in LED's...You be the leader, I'll be the follower.

 

[wontonflip]

Yep! I'll be posting a lot! Once I start building the actual unit, that will be a new thread, so I can start it clean. I'll probably test this light on my shrooms, which are currently in the sump, feeding off a regular 8watt t8 ligthbulb, but doing ok, since the light is close to the shrooms. I want to see how they react to the LED.

 

[project5k]

as successfull as your tests seem to be going, your making me second guess building my 16 bulb t5 fixture...

 

[wontonflip]

Hehehe...well, seeing the light w/ the naked eye is one thing, but the true test will be getting the actual par readings in the tank.

 

[mdenny]

man thats bright how manny r u going to put on the tank?

 

[dcantucson]

I'm surprised as to how much light that little thing produces. Wow! Would those work for corals?

 

[wontonflip]

man thats bright how manny r u going to put on the tank?

Well, the tank is 72 1/2 L x 18 1/2W x ~24h. So originally, our plan was to do around 20 p7 LEDs, and 8 blue LEDs (maybe less, since it's not a necessity anyway). Something like this:

But now, seeing how bright it is, we will reconfigure it, and we'll end up using less LEDs, saving some money. The guys in RC could argue and say that the crees are cheaper....but he ends up using more crees to light his tank than I would with the p7s.

All this is just theory. I am not good at visualizing. I never know how things will go until we actually try it out.

I'm surprised as to how much light that little thing produces. Wow! Would those work for corals?

Well, if the p7s output quality is as good as a MH or T5, then I don't see why not. Unfortunately, I have no plans on keeping corals, because it's means more work and dosing for me :) I plan on just doing mushrooms, as I had good luck with those in my 10g. But if I can get the PAR readings, I don't see why other reefers can't use p7s.

I haven't even tapped into that led's full potential yet....that was just running off batteries! :)

 

[PRC]

I'm not a mathmagician but that's like $420.00 in light bulbs!...How much do you tink the end product is going to end up costing? Are you going to use dimmers on the LED's?

 

[wontonflip]

Final cost will be around $600-700 (thereabouts -- so about as much as a good MH or T5)..except mine will have long term savings -- don't forget that LEDs last a long time. They could last 1-2 years at least. The site I buy these from also offer discount on 3+ orders. And the other thing is that since it's a DIY project, I'm not spending $600-700 at once....it's over time, as I have money to buy my parts. I'm not concerned about the cost, really. Think about how much you will spend in bulbs in one year for a MH or T5. I will be spending $420 in the start, and as each one dies out in 1-2 years (hopefully), it will only cost me $15 at a time. You have to look at the big picture. Don't forget the money I save in electricity over time.

Plus hubby has a lot of the parts already.

Yes, we will use dimmers.

 

[tankedchemist]

I can't watch the video at work, but do you know if they've measured the spectrum of the bulbs you're using?

 

[wontonflip]

Scroll up to the 4th post or so....I put in a pdf file with its specs. It's pretty white. It says it's 6500K

 

[bjohanson1234]

Looking good.

I was just looking over the PDF. The typical forward voltage, or the amount that it uses, it 3.6 volts with a max of 4.2 volts. So dont put more than that on it or else you will most likely burn it out. There are ways of using a resistor to drop the voltage down to usable voltage from the 12 volts of the PC PSU. You could also use the 3.3 V off the power supply.

 

[wontonflip]

The RC build thread uses buckpucks, which I'm guessing regulate the voltage it lets through.

I freaked cuz the first battery we tried was a 9V and it friggin' blinded me, it was so bright! That's when I suggested we piggy back 2 AAs @ 1.5v per battery.....that did the trick, and the pics are the result.

 

[bjohanson1234]

Buckpucks actually regulate the amperage. That way if the resistance of the LED changes because the temperature changes, you are still getting the correct amps going through the LED. It keeps it at the same brightness/color temp. If you look at the specs, it shows you what happens at a specific current. So the use of buckpucks eliminates any varying brightness or color.

 

[wontonflip]

Cool, thanks :) I'm going to be ordering my LEDs next week. I considered ordering 1 cree just to do a side by side.

 

[Ulta]

Correct me if I'm mistaken but you should only need 1 LED every 13.8" If you wanna cover the bottom 1/2 of the tank with >90% intensity. Thats only ~6 LEDs not 28.


Unless there are some factors in play that I'm not getting...
Like if it takes more than 1 LED to get the desired amount of Lumens or
There is a greater loss of light through the water than through the air.

 

[Ulta]

Ah, I see now each LED produces ~700 Lumens.

So now my question is how many Lumens are required in a reef Aquarium?