Anybody running a DIY LED for a planted tank?

[Jstdv8]

I'm thinking since it seems that the colors the the plants require are not the pretty colors that we like to see in our tanks that I'll have to go with as many LED's as I need for good plant growth of any plant out there and tehn also suppliment in some other colored bulbs in between so that I can mold the overall color into something I'd like to look at.
Being a SW guy I'm kinda partial to blue more than yellow and red, but alot of you FW peeps seem to think its un natural. As I've never seen a planted tank with bluer lights on it I guess I can't really judge for myself unfortunatley.

I was considering buying from Rapid LED or Steves.

This is not a for sure thing as I may jsut wait and see if they advance the lights a little more towards FW stuff since the SW is starting to kinda get set on the right path.
This time last year people were making LEDs for SW like crazy, but alot of the technology has changed for the better in even that short time.
Sometimes I wonder if I'm kiding myself by getting in to early and not waiting for the technology to be more perfect for what we want.

 

[DoctaQ]

i guess the ultimate thing to wait for then is a high cct high cri led that doesnt exist yet, they do have high cri in 2700k

 

[smitty]

Subroto welcome to Aquaria Central. I really appreciate all the knowledge you guys are passing on. It gives me a little confidence that it is something I may be able to handle soon.

 

[Subroto]

Waiting for even something marginally better would be, IMO, worthwhile, js. We may not see a FW dedicated LED soon, but it is quite possible that light in the green spectrum is added to a new generation LEDs even at the cost of that spectrum being "wasted" in terms of the plants' benefit. Inherently, the LEDs are so energy efficient, I really would not mind (and I doubt, any planted tank enthusiast would) a little waste if that brings out the beauty of the green in all its possible shades like a full spectrum can.

I wonder Doc, whether mixing some green LEDs with warm white, neutral white or even cool white, would give us that effect rightaway. I mean, the way blue LEDs are mixed with whites in the reef tanks to get the blue effect.

 

[DoctaQ]

mixing in some warmer colors might do it without wasting too much light, honestly it seems to me kinda silly to put greens which add almost no growing power to the light

 

[DoctaQ]

the only full spectrum light source is the sun btw
the cri of most aquarium bulbs above 67k are usually dismal

 

[Subroto]

Thanks smitty for the welcome note!

So, Doc, if we can't wait and decide to have it what is available now, in your opinion, we have to restrict ourselves to warm white LEDs with K rating of not more than 6700 K, right? I agree. However, I would restrict myself to 6500 K to get even a little better CRI.

BTW, is there a place where I can get some technical specs like the spectrum graphs, CRI values etc. of the various Cree or Luxeon LEDs?

 

[DoctaQ]

the datasheets of the leds will have spectral distribution graphs and other measurements

if i had to put a fixture together for high cri as well as power, i would probably look for some of the high cri xp-g warm whites(2700k), then some regular cool whites to balance it out

maybe a 1ww to 4 cw ratio and see how it looks, seeing as something like this has not been done yet, i would definateley drill and tap my heatsink so that i could easily remove and replace leds until i find the right ratio.

personally..this is extremeley nitpicky, i would put the color of a regular led up against a 67k cfl, and maybe even a pc

 

[Subroto]

Hmmm....quite tricky. But I think we do not need to go to that extreme. If you look at the datasheet of Cree xp-g, the relative spectral power distribution graph shows promising quality in warm white which has a CCT range of 2600-3700 K. It gives you a peak 70+% radiant power in the band of green spectrum (500-560 nm) that comes to almost 62 lm at 350mA. The 85 CRI white and the 90 CRI white have more or less the same quality except that they come in 2600-3200 K range. IMO, any of them would provide us the visual satisfaction that we are looking for, without all the permutations and combinations of different LEDs. But often the theory does not translate well into practice. It would be better if a sample unit of, say, 4 or 5 LEDs is tested to see the outcome before embarking on the full project. After all, seeing is believing!

 

[DoctaQ]

the issue with that is that you probably dont want a tank that is 2700k, you will need some cooler color to bring the color temp up