You need more, but it's not so you can keep sps frags. It's so you get complete coverage of the tank with uniform lighting and color. For that tank, 24 LEDs in a 12x2 array is the normal recommendation. It's more than enough light for whatever you like, and divides into the popular drivers easily (4 Buckpucks or 2 Meanwells)

What are good options for UV-LEDs?

Evil, how do the PAR38 bulbs compare teh the Maxspect fixtures? Also, is it difficult to change the optics on the
PAR bulbs? Also are the LED's replaceable?

Don't know yet. All the potential ones are very expensive ($50 or more)


Apples and oranges. Both achieve the same results, but in different ways. Changing the optics isn't too hard, but you do have to be careful not to damage the LED. The LEDs are not replacable. They shouldn't need to be though.

Hey Evil - Do the LEDs in the Par38's give off more par than say a 12 LED retro? To get to 21 watts is each 3 watt LED run at a high wattage. I ask because the Par38s cost about the same as a 12 LED retro. Granted one would have to buy the heat sink and soldier it all up, but it seems to me that I would be getting more than double the light for about the same amount of money.

Any insight would be great, because I really like the Par38's and think you have built an amazing product. I even bought one to test out and really like it.

Pete

Peak performance can be the same. The major defining difference is that the retro is more even in light output while the PAR38 is a spotlight and the PAR drops off the further off center you go. The only way to get more even light is to use more LEDs.

I just can't let go of the Par38 alternative. It would be perfect for my situation, however I am having issues with the fact that other than the lens, nothing can be replaced. If an LED goes out a year from now it means purchasing an entirely new bulb. Aside from the cost, it may not even have the same housing so now it would be a mix and match issue. Maybe I am overly concerned, since I have no experience with LED lighting and reliability. Evil, can you comment on the quality of this bulb?

For anyone that has followed my work over the last few years, they know I don't deal with iffy products. I looked for a very long time to find the best lamp to build off of. The heatsink on this one is the best I have found by a long shot. What that means is that the LED temps are a lot cooler than on similar lamps, which means the LEDs will live a lot longer. I don't see it being an issue hitting the 50,000 hour mark. Now, that's not to say that an LED won't fail from manufacturer defect. If something like that does happen, while the end user may not be able to fix it, we (Me/Chris/Nanotuners) will, and could fix it for a nominal charge. There shouldn't be a need to replace the whole lamp, unless you dunk it or something silly like that Basically what I'm saying, we will take care of you no matter what.

Thanks!

Evil,
Since you know lighting more than most, if not all maybe you can help me with this. I have recently been having an issue with jumping fish on my rimless. I have lost a couple over the past few months. I hate to design a net to put over it because of the appearance but if I need to how much light will I lose. Most of this material has about 0.25 holes and is very thin. I also wonder if it may not help to defuse the spot light effect from the PAR38 bulbs.

.25" grid netting won't block or diffuse the light at all.

Ok since I am procrastinating my led build. I need a question answered. My current lighting is a 60" hamilton tech 2x 250w mh w/ 2x 60" vho actinics. I am probably going to go with the cree /meanwell combo for lighting in the end. However I stumbled across 10w 900lumen 7500k 8 meter projection waterproof floodlight fixtures(a call to the manufacturer revealed flat panel chip led emmiter was used) How many of these units would I need to light my tank? btw they also have royal blue floodlights also. I was thinking 4 cool white and 4 blue staggered on timers (2 blue dawn/ dusk and the rest for for daylight photo period.

they have a 120degree projection angle.

Without know a little more about the LED, I couldn't tell you. A datasheet would be great.

Led Source : 1PCS 10W High Power LED
Lumen : White 800-900, Blue 400-500
CCT : White 6500-7500K, Blue 470-475nm
Beam Angel : 120 Degree
Project Distance : 8m
Size : L115*W85*H95mm
Material of Shell : Aluminum Alloy
Weight : 2.2Kgs
Rotary Angle : Vertical (-90。C-+ 90。C)
Input Voltage : AC85-256V
IP65 Waterproof Rated

I just e-mailed them for a data sheet. but here is the info I have.

Here is the email response I got back.. What questions should I ask?
Hi, Andrew

Thanks for your email, and we are sorry that we don't have the data sheet of this led fixture.

Please let me know if you have any questions about this flood light, we will try to answer you the questions.

Regards
@#$#@

That brings up concerns for me, but that's not to say that it won't work. My other issue is that the cheap 10W and higher LEDs have a much higher failure rate over time.

You would have to pair a white and a blue together, but you would probably need about a dozen groups split in two rows to cover the tank.

a dozen groups of these? lol

And a dozen blue. This is just an estimate though, as I've never used them before. You would be using a lot more Crees than that, but it would have much more even light distribution.

Evil, got a PAR output question, since you've tested these before.

I'm about to max out my Meanwell with 13 rb's. No optics.

They are on a 2" wide, 24" long heatsink (will add two fans on it). They are spaced about 1.5" apart in a zig-zag formation.

This is my actinic supplementation. Without optics, the blue is spread out over the tank just fine (for my taste... the back gets less but everything else gets plenty).


How much PAR, as 12" and 20", do you think this would be throwing, without optics?

This is supplementing a 250 DE Phoenix, so it will certainly be light (and blue) overkill, but I'm growing mostly SPS anyhow. I may end up changing the bulb over to a 10K EVC bulb, which is is like 30% higher in PAR than even the 14K Phoenix but much whiter.

Now, these are really rough guestimations, but at 12" I would expect about 150-175, and at 20", 75-100.

Ah, thanks, a ballpark is good enough for me . Those are slightly higher than the numbers I got from a 4X24 Nova Extreme. (ie, 96w consumed vs. ~50 watts consumed), not to mention looking cooler.

Gonna grow sunspots on the sandbed with that Phoenix. .

When dimming buckpucks with Arduino, where do the CTRL and REF wires need to go? I'm looking at dimming 8 of them independently on a Mega...

So guys, I've read the entire thread today. Lot's of good info. I'm ready to take the next step and cost out what I need for my tank. I have a 100G that's 48" across and roughly 24" deep I believe. I'm currently running 2 250 watt 14K's and 2 95 watt T5 actinic's.
I believe I'll need to alternate blue and white to achieve this same temp/color on the tank?
What configuration should I be looking at? Seems like I'm seeing something smaller than 2" center for the led's across the entire length of the tank.

sq

Quick question,
I have a 110v AC to 12v DC Power Supply (http://www.coolerguys.com/840556087977.html ) as power supply for my 12V 120MM fan.

Will I be able to add additional 12V 60MM fan If I use a 4pin Y cable? (http://www.newegg.com/Product/Product.aspx...N82E16812189062) Will both fans get 12V if they are running parallel from the power source?

I dont know the answer to your question but I wanted to say nice IS250.

Phew!! Back from Reefstock!


The simple way is to just connect the CTRL wires to outputs on the controller. The controller isn't protected at that point though. A better way is to use Fig. 14 on page 7 of the datasheet:

http://www.luxdrive.com/downloader.php?id=4


Alternating blues and whites in a 50/50 mix will sit you at a 14K color temp. Your final color temp can be set with the drivers (providing you use dimmable ones). For a tank of your size, you will need an 18x6 array to fully light the tank. Add 60 degree optics to that to get light levels similar to what you have now. Spacing will be 2" on center per LED per row, and 3" per row.


Running in parallel adds current. All devices see the same voltage.

I have ordered 24 Cree XR-E LEDs, 12 CW and 12 RB, wich I am going to use for my DIY LED build.
Will this be enough to cover my tank, wich is 26.2"x14.6"x10.4" (LengthxWidthxHeight)?

More than enough.

How high off the water surface should a PAR38 be for a jbj pico? Do you think I will need the 80 deg optics to achieve max spread?

What do you think the measures on the heat sink should be?
How far appart can I mount the LEDs without getting the "spotlight-effect"?
The LEDs come with lose 80 degree lenses. Should I use them, or will that fry my top SPS, considering my tank is only 10.4" heigh?

80's over that tank isn't so much for spread, but to lower the intensity to more usable levels. Start with the lamp about 12" over the tank and adjust as needed.


If you want to use all the LEDs, then go with an 8x3 array with no optics. Spacing will be 2" on center per LED per row, and 3" per row. With that setup, you will need a heatsink that will cover a 16x8" area.

This sounds silly but can I use this wire?

http://cgi.ebay.com/TXL-20-AWG-GAUGE-ORANG...334271505937948

-Dave

Yup. That's a lot of wire though

Whats the better option (talking about heatsinks) for doing LED strips of Royal Blues just to supplement T5? I want 12" modules.
Using aluminum "L" or angular channel
1"x1" or 1"x1/2" squared aluminum tube
getting any profile heatsink from heatsinkusa (lets say 8.4" x 12" and have it cut at 1" wide) final pieces will be 1"x12"

OR just getting 8.4 profile x 1" which is cheaper $2.25 but the fins run the short side

And last, 1/8" thick aluminum sheet (again 1"x12")

Thanks!

Much of it depends on the drive current, and the spacing and number of LEDs per strip. With the LED actinics I made, 3 at 700mA was at the limit for comfort for me with 1-1/4" angle 3/16" thick. The more surface area the better. Tube isn't a good idea unless you have airflow down the middle to remove trapped heat.

I converted my BC29 to LED about 6 months ago. 13 cool white and 13 royal blue on Meanwell LPC driver. Just last week I noticed the tank looked dimmer. Turns out that only the blues are dimmer, while the whites are fine. There are NO dimming switches, full power all the time. Any ideas why just the blues are dim?

Tough to say. Two possibilities come to mind. First, it was a thermal issue and the LEDs have overheated. Second, the driver has failed and the output has dropped. Considering that all the blue LEDs are dim, and the whites seem ok, overheating seems unlikely. What I would do is check the voltage and current output of the driver to see if it's still in check. Another thing you can try is to swap the drivers around and see if the problem follows the driver.

I already tried swapping drivers. That's not the problem. I did get the blue to come on "high" again. They blinked bright,dim,bright,dim, etc. Then eventually just dim.

Also when the blues are on by themselves, the white LEDs have a very slight glow.

Then there may be a faulty LED. Check the voltage drop across each LED. If it way outside the normal 3.3-3.8v range, then it could be bad.

Thanks evil. Im thinking 4 leds per 12" module ran by meanwell lpc35-700 every 3 pieces. Spacing between them is given cause 12" length and 4 LEDs= 3" between each. How does that sounds? I talked to Russ from heatsink usa and he told me cross cuts are easier and look nicer but I still want to do it 12" long

hi evil-

i need help. i've tried to read as much of this thread as possible but my head is swimming.

i'd like to convert my ~26 gallon from T5 to LED.

tank dimensions 24" x 14" x 18" tall. currently running 4x24W T5 Tek Light. i can currently grow SPS, but i'd like to grow some of the more light-intensive species.

i'm thinking that 36 3W LED (18 Cool White Cree Q5 XR-E, 18 Royal Blue XR-E) might be the way to go. here are my questions. ideally i'd like dimmable drivers to be able to adjust the relative color temp, but in a pinch, i could do without them.

1) do you think this will be enough light?

2) is there any way to retrofit this into an old CurrentUSA Orbit 2x65W power-compact fixture? i've got an old one lying around and i like the look of it... plus it's already got a fan and a splash guard. one thing i'm concerned about is "usable" space is only around 5" x 20" (x 4" high). i'm worried that even if i could fit all the LED's in, i might not get enough light in the front or back of the tank (the tank is 14" front to back, but the CurrentUSA is only 5").

3) what degree optics would you use? the tank is 18" tall. most of the SPS will be higher and towards the middle (maybe some near the back wall, but definitely not too close to the front glass), but i would like the option of growing some lower down. incidentally, with the Orbit fixture, since it ran pretty cool and my water surface is pretty calm, i am able to keep it ~ 2 inches from the water surface, so the absolute deepest the light needs to go is 20 inches.

4) rapid-led's offers a 36 LED dimmable kit for around the same price as a max-spect G2-110W (which is non-dimmable and uses inferior semileds, but the LED's are user-replaceable with Crees, and it's got a snazzy housing). should i just bag the DIY and go with the manufactured solution, replacing with Crees as LED prices come down? are there other good options i am overlooking? i can't afford to spend $800+ dollars for a "high end" solution.

sorry for the long post. any advice would be greatly appreciated!

Stick with a beefy L or C channel at a minimum. With only 4 LEDs at 700mA, you should be ok.

1) More than enough. You could easily get away with 24 LEDs in an 8x3 array and still get great coverage and lots of intensity.

2) The width is the killer. If you go with my 3 row suggestion, you need a little more room. It could work, but it's pushing it.

3) Shouldn't be a need for optics for that height.

4) LED prices won't come down in a hurry, so don't hold your breath waiting for affordable Cree replacements. DIY gives you so much more flexibility, and potentially more performance. When you DIY, the array is always best suited for your tank, while commercial options are always built with compromises to fit a number of tanks. Anyway, with only needing 24 LEDs and one less driver, the DIY approach becomes much more affordable.

hi evil

i have been reading throug this thread for a while now but i only joined this forum tonight.

i am busy planning to build a pico type tank that is 10" x 13" x 12"

i am planning on using cree XR-E led's but have no idee how many or what power source i would need.


i want to be able to keep a clam and sps. so it needs lots off light.

i then also need to mount the light unit a bit above the tank, like a lighting pendant.


also want to be able to dim the blue lights, so i can figure exactly what colour is my favorite.


could you maybe help me by telling me what equipment i will need to buy to build a suitable unit.





ps. i am from south africa and we are light years behind you guys but i have got a cree dealer close to me.



any help appreciated


regards

For that setup, I'd go with 8 LEDs in a 4x2 array. Go with 50/50 white and royal blue, and that will give you a starting color temp of about 14K. As for drivers, that will depend on what you can get, or what you are prepared to order from overseas. Just look for something in the 700-1000mA range that can take 4 LEDs and is dimmable.

Optics will depend on how high you want to mount the fixture above the tank. Anything beyond 8" over the tank should need optics.

Thanx alot for your very fast reply and help so far. Is it possible to maybe up that to ten led's 5 white and 5 royal blue with the same drivers, or am i limited to 4 per driver.

i dont think i will have the fitting as far even as 8 inches away.


with 8 led's will i be able to keep sps and so forth?

I checked it out on a multimeter. the blue LEDs pulled less than 2.5 volts each while the whites LEDs pulled 3+ volts. Tried swapping drivers and got the same readings. So the problem did not follow the driver.

The number of LEDs doesn't really change the ability for the array to keep sps or not. The more LEDs you have in the array, the better your coverage is. 8 LEDs is the minimum I'd recommend that you use for full coverage of the tank. Going to 10 LEDs will only improve coverage and color blending, not intensity. The number of LEDs you can run will be dependant on the driver that you pick.



Hmm, that's odd. Were all the LEDs about 2.5v, or were there some that were less? With the problem not following the drivers, there must be an LED in the string that is causing the issue, whether it is faulty, or somehow shorting to the heatsink. Why it would do it all of a sudden is odd.

Only 3 of the blue LEDs run 3ish volts. The other 10 blues run 2ish volts.

Check for shorts between all solder joints and the heatsink just in case.