LED's by Ecoxotic?

[Cyclesafe]

As it's time for me to replace 2 96W 6700K CF bulbs for $68, I was thinking that for a few pennies more I could get one (or two) of these 13W 8000K LED fixture(s) for $99. They seem compelling:

• No scary DIY electric wiring around the tank
• 13W (or 26W) rather than 192W - significant power bill savings!
• Would make my wood canopy a tad lighter
• Reflector edges are contained so I would not cut myself on sharp metal edges
• The color would be more pleasing to me, as a human
• The shimmering effect would also be esthetically appealing
• Virtually no heating of the tank: there would be less temperature variation when lights are on and I wouldn't need a fan in summer (no more mid week top offs!)
• Bulbs last ~10-20X+ as long as compact fluorescents
• I wouldn't having to worry about generating hazardous waste (used mercury-containing CF bulbs) or chauffering dead bulbs to the HW accetance station at the dump.

Of course, I don't know how they'd function as a fixture for a low light 120 gallon planted tank. And of course, that's rather important.

I know what Ecoxotic thinks. What do you guys think?

[pdavis41]

They don't state what kind of light (lumens) output they provide. That is the only huge drawback that I can see.

Since you are running low light I could see a couple of these working for you. How long is your tank? You would need at least as many as it would take to cover the length of your tank. I'm guessing they are 1W LED's as there are 12 diodes for 13W. Can't really guess what PAR to expect until you can figure out what the output of the lights will be.

But they do look promising and easy to install if they can put out enough light!

[Cyclesafe]

4'x2'x2'. I have sent an inquiry to Ecoxotic asking for PAR values. I'll report back when/if they respond.

[SuperColey1]

They look OK however the maths doesn't add up!!!

[*]13W (or 26W) rather than 192W - significant power bill savings!

Yes you will save power with high power LEDs but if these are 1W x 12 how are they 13W units? Are they overdriven? If so they will burn out quicker

[*]Would make my wood canopy a tad lighter

Most definitely.

[*]Reflector edges are contained so I would not cut myself on sharp metal edges

Why do they need reflectors? LEDs only push light down and then lenses focus them. Even if the reflector is there to catch the sideways light that is much less efficient than lenses which is wierd. Lenses are cheaper than reflectors by a long way. Lenses direct all the light downwards much like the cone type reflector in a torch.

[*]The shimmering effect would also be esthetically appealing

The shimmering is nothing to do with LEDs. It is to do with multiple light sources. 12 smaller flourescents will give you shimmer. 2 flouros raised high enough will

[*]Virtually no heating of the tank: there would be less temperature variation when lights are on and I wouldn't need a fan in summer (no more mid week top offs!)

Anyone who knows high power LEDs knows this is wrong. they give off massive localised heat and then we use heatsinks to draw it off. Often couple with a fan. Mount a few of these on an aluminium bar and it will bend with the heat.

[*]Bulbs last ~10-20X+ as long as compact fluorescents

Exaggeration to say the least. Say 3x CF and 1.5-2x linear flouro on electronic ballasts

Of course, I don't know how they'd function as a fixture for a low light 120 gallon planted tank. And of course, that's rather important.

2 over a 120G is hopeful to say the least. You're going to need approx 1WPG LED to match 2WPG of CF.

They don't state what kind of light (lumens) output they provide. That is the only huge drawback that I can see.

Lumens is no use for us at all. Lumens is only what we can see, nothing to do with PAR. Add to that LEDs give out less Lumens per W but higher PAR!!!. a 75W Solaris gives out 85% the PAR of a 250W MH!!! It gives out 110% the PUR.....Ouch

Since you are running low light I could see a couple of these working for you. How long is your tank? You would need at least as many as it would take to cover the length of your tank. I'm guessing they are 1W LED's as there are 12 diodes for 13W. Can't really guess what PAR to expect until you can figure out what the output of the lights will be.

As a basic guide just work out you need a third to a half of the wattage of the CFs to match them. Also I would say you could use less than 192W of CF over your tank for low light. <1WPG flouro is low light IMO. I used to use 0.9WPG flouro I average 0.86WPG now (LEDS are staggered over the photoperiod) however I have the LED luminiare 15 inches above the water level compared to the flouros which were 4 inches above the water level.

But they do look promising and easy to install if they can put out enough light!

Oh they'll put out wnough light. less lumens but much more light (PAR). Lumens and Par don't move up the scale together necessarliy. Think pink lights versus green lights. The pink light is dimmer and less lumens but will be about the same PAR as the green.

Summary.

the units look OK to me however I think their marketing team has had a field day or too many red bulls. or maybe something more illicit. lol.)
Efficiency could be much better by using lenses too. 5 or 6 should be fine with lenses (If they are indeed 1W), no idea without but I would guess you lose light that way (They will focus all the light down and penetrate better.) The 13W into 12 LEDs seems a little strange to me. Why marlet something as efficient and last a long time then use inefficient reflectors and overdrive it making it not last as long as it could?

My Tip.............Make your own. It will be better spec, tailored to fit and something to show off.

AC

[Cyclesafe]

AC,

You obviously know a great deal more about this than I and I appreciate your analysis. Where can I go to get the best instructions for a DIY project?

Also, your points about running one 96W CF bulb are well-taken. That's what I'm doing now - backing off from the four I used in the past.

Meanwhile, The Ecoxotic people came back with the following:

Dear Mr. Hayford,

Thank you so much for contacting Ecoxotic and showing interest in our LED products.

Although we understand many hobbyists have been told an aquarium requires a certain number of watts per gallon (WPG), it really is not a measurement of light output at all and we do not compare LEDs to CFs in this manner. In addition, PAR in CF’s will be very dependent on the color spectrum, ballast/driver used and manufacturer of the lamp.

We can tell you our Panorama Modules use 135 lumen/watt LEDs and most planted aquarium hobbyists use our 8,000K Panorama Modules. For a heavily planted 48” x 24” aquarium, we would recommend using 1 module per 12” (therefore 4 modules.) This will provide the same amount of light your currently using with 2x96w CFs.

If you have any other questions regarding our products, please do not hesitate to contact us. Once again, thank you for showing interest in our products.

Sincerely,
The Ecoxotic Team

[SuperColey1]

Just quickly a link to mine however it is on barrreport somewhere too. Mine is a bit of a non electrical knowledge effort in terms of power. Others would probably use a single plug and program a board to do the stagger where I use 5 DC adaptors with timers instead.

http://www.greenneedle.co.uk/LEDMKII1.html

Like I said above they are a little on the optimistic side in the reply they sent you.

PAR is light and nothing to do with spectrum. Lumens are affected by spectrum.

I think if they were using lenses then 4 is possible but why they are using reflectors I do not know.

AC

[nipat]

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PAR is light and nothing to do with spectrum. Lumens are affected by spectrum.

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Doesn't actually PAR depend on spectrum while lumen does not?

[SuperColey1]

An example of Lumens with Spectrum for a like for like LED unit just different colours:
Warm White: 3700 Kelvin; ~ 550 lumens - Yellowish Light
Natural White 4100 Kelvin; ~ 600 lumens - Slight Pink Light
Daylight White: 5500 Kelvin; ~ 650 lumens - Pure Day White
Cool White: 7000 Kelvin; ~ 650+ lumens - Bluish Light

source:
http://www.ledtape.com/LED-T8-Light-...-2-nw8w180.htm

If PAR ran with the K then it would mean if we use X colour we would need more LEDs than if we use Y colour which isn't the case as far as I know.

Its the (not so old) use what colour you like statement. If spectrum affected PAR we would be saying use X colour as it gives more PAR for less wattage consumption.

I would forget about the lumens figures on most light sales websites. They tend to put the same lumens on all the colours of a particular brand from what I can tell.

AC

[Jim Miller]

Both are measured with spectal effectiveness: lumens for people PAR for plants. Spectral curves are different.

Jim

[nipat]

Both are measured with spectal effectiveness: lumens for people PAR for plants. Spectral curves are different.

Jim

You are right. I've forgot that lumen/lux is derived from human vision.

If PAR ran with the K then it would mean if we use X colour we would need more LEDs than if we use Y colour which isn't the case as far as I know.

AC, not quite. Different spectrum combinations can yield the same color for our vision.
PAR does has spectrum involved. Two light sources with same color can give different PARs.

Kelvin is poor way to communicate. Because we don't know what spectrums combinations in it.
It's also a poor way to communicate color.

Look at page 2, 6000K can be yellow or pink. And by the same way, 10000K can be blue or pink.
http://docs.google.com/viewer?a=v&q=...w8XGCUa-5nE_5w