DIY led for 49gallon tall

[butwa20]

i want to make a led light fixture for my tank it is a 49 tall its 20" tall 36" long and 15" deep i want to know how many led's ill need to have a good set up with like 6watts per gallon. also i know most led's are 3w per light so u really need 100 of them to make your system 300watts?

[txg8gxp]

Rule #1, don't pay attention to wattage. It just don't add up anything like any other lighting system. If using cree 3w leds, I would say something around 40 would be plenty. Yes, that's only 120w but it would be plenty of light for that size tank. I only run 48 on my 57g and 12 on my biocube29.

[butwa20]

how many can u wire up to one driver

[butwa20]

and also do u think i should use the longer strip heat sinks or the box ones?

[txg8gxp]

how many can u wire up to one driver
That depends on the drivers, the most common...Buckpucks can run 6 leds and some meanwells can run up to 13-14 leds. There are some new drivers from nanotuners that are dimmable and can run up to 15-18 if I remember right.


and also do u think i should use the longer strip heat sinks or the box ones?
That is up to you, as long as you have enough thermal mass to dissipate the created heat you are fine. I personally for DIY like the idea of NOT relaying on cooling fans, so I would want a larger heatsink. Something in the 28"x8" range would be good IMO.

Here is some basic info if you haven't seen it yet. http://www.maast.org/showthread.php?65087-LED-Presentation

[butwa20]

what do u think if i did 30 led's 15 white and 9 royal blue and 6 blue? I have heard mixing the b with rb makes for a nice look. if i need 40 led's ill be able to add them later with the setup i am thinking about.

[txg8gxp]

That will be alot of white leds or less you are going to run XRE series or XP warm/neutral whites. If running XPG cool whites I would run 2 blue/royal blue for every cool white. That would give you around a 15K look. Yes, I would run both the blue and royal blues. That just adds a better color mix and a larger color spectrum. The RB are 450-465nm and the B are 465-485nm.

[Europhyllia]

I did half and half on the white/blue ratio. In retrospect I should have also done a combo of B and RB. But I do like the 50:50 combo in regards to warm/neutral whites to blues. In fact for the seahorse tank I could have even seen a higher ratio of whites work well.
I am not into deep blue tanks though so even on my reef tank I crank the whites up to 70% and leave the blues down at 40%.

[butwa20]

Which ones are the ones I should use for the moonlight effect?

[Europhyllia]

Personally I like a mix for that as well.
I only use the moonlight effect on the AI fixture (not the DIY) and on that I have it at 1% white, 2% blue, 2 %royal blue
I don't have automatic dimming on my DIY fixture and skipped the moonlight on the seahorse tank where the DIY fixture is.
If I had to select only one color I'd go with the cool blue. It's sort of greenish blue. I could imagine this looking the most natural.

Personal preference though I am sure!

[txg8gxp]

I like to use the blues for my moonlight. Like karin said, the greenish blue looks alot more natural to me.