newbie314

i was commenting on thre led but the original post is old so I wasn't expecting a response

Fortuna Wolf

You should check the spectral distribution of the LEDs, but remember, plants like blue and red and don't utilize yellows and greens to a significant extent. Anything from 400-500 nm, and then 625-675 nm as a rule of thumb. The common red LEDs are not optimal, though you can get red LEDs that are in the correct range.
Look for bluer white LEDs and mix them with some reds if you actually want a useful spectrum.

The white LEDs have a yellow phosphor and pretty much lack the red... Also, the high lumen rating is usualy due to the very narrow beam, ~25 degrees usually. I'd double up the LEDs and put in a variable resistor so you can dial in a brightness.

mulita

Very nice Fixture!! Excellent array. However, as Fortuna Wolf mention here, the spectrum could be an issue to have this kind of fixture fully functional. This is the way to go if a combination of led can produce the right espectrum. Nice, nit, low enery consumption and low heat. Definitively the future.

El Exorcisto

Question, do you get "halide shimmer" from LEDs since they are each a spot source? I'm thinking about playing around on a 10 gallon and I'd be adding a row of ~625nm red LEDs to balance out the blue side of the white LEDs. I might do a few greens too, just to make the plants POP. Would 100 25K MCD whites, 20 ~625nm reds, and 20 greens put me at enough light to be happy?

Volenti

My luxeon led array (approx 1'' spacing) get's shimmer, though I don't know about a the effects of a more densely packed array, may not shimmer much.

Jedidiah

So are these actually effective for growth and saving power?

I'm running a coralife setup that's 3-4wpg, it'd be really cool if we could replace them with LEDs.

Heat would be less too, so no fan noise as well!

Cool idea!

mcjosh13

Taekwondodo, your calculations are way off. "1300 lumens of light for less than 1 watt" is impossible. If a LED was able to be 100% efficient (in actuality they are closer to 15% luminous efficacy,) It would produce 683 lm/W. That is the maximum amount of light that can be produced from 1 watt of energy. The best LEDs that you can get are able to get just over 100 lm/watt.

Compact florescent lights are supposed to produce around 60-70 lumens per watt so the LEDS do offer an advantage here. Also fluorescents radiate light in all directions so there is much greater losses and the light does not penetrate into deeper tanks very well.

An LED fixture radiates all of its light in one direction and with some focusing optics (40 degree collimator's are used in some commercial products) the light can penetrate deeper tanks very effectively similar to metal halide lights.

taekwondodo

I trashed this project well over a year ago and went with 2x9w AHSupply PCs.

It seemed to get dimmer rather quickly, and didn't really provide any great growth - that, and my 5g tank at work gets a lot of neglect (and accompanying jokes from co-workers, "Hey, are there any fish in there?").

While I think we're all confident in LEDs as a future lightsource (reefers are using them very successfully, as are some in the "alternative" growing arena) - The cost/time/benefit for DIY I'm not sure is there yet.

- Jeff

mcjosh13

The problem with basing those assumptions off of your DIY LED project was that the 10mm LEDs that you got off ebay were of low quality and are not suitable for such a project. These were really the LEDS of the past where as the newer high power LEDs (like Crees, Seouls, and Luxeons) are much better suited to a project like this.

But then again with florescents being very effective, relatively cheap and time tested, the move to LEDs would only be for those who like testing out and experimenting with new technologies and not for those who just want an effective time-tested DIY setup. Many questions must be answered before LEDs can take this role (ie. exactly how many LED lumens are needed to equal florescent WPG rule (the use of optics will greatly effect this in favor of LEDs), what wavelengths and color temperatures create the best plant growth, what color combinations create a natural look and bring out fish and plant colors like high quality florescents do...etc.)

After enough people have experimented and data collected, LEDs will begin to replace florescents in the planted aquarium. The good thing about a DIY LED project is that they are easy to build, high quality parts are readily accessible, and even a beginner can put together a high quality set-up.

taekwondodo

I knew that going in - trying to do it on the cheap. But if you take a look at the price of higher-power LEDs, OUCH! (even now, and I built this more than a few years ago).

The other point I was making was that LEDs are already proven for both Reef Tanks and Dope Growers - but the price/point isn't there yet for DIY, and the guys that buy these for reef tanks are the few who like to buy the new widget every couple of years and have the cash to do it.