LED conversion

number1gsxxr

number1gsxxr

Member
Very cool build. How did you determine what the spectrum would be? Did you just pick half blue and half white? Are there any guidelines for determining the number of LEDs per tank size? I'm upgrading to a 75 from a 46-gallon. 48" vs 36", so I'm in need of a new light fixture. Maybe I'll do a custom LED light for my new tank.
 
mastertech

mastertech

Member
Originally Posted by number1Gsxxr
http:///forum/post/3201971
Very cool build. How did you determine what the spectrum would be? Did you just pick half blue and half white? Are there any guidelines for determining the number of LEDs per tank size? I'm upgrading to a 75 from a 46-gallon. 48" vs 36", so I'm in need of a new light fixture. Maybe I'll do a custom LED light for my new tank.
well the spectrum has been specified by generations of reefers. 460nm is the normal blue lighting that actinics are tuned to but actinic PC, CF, T5, MH etc will loose there tune and give out the bad spectrums. leds will hold the specific spectrum longer (up to 50,000 hrs vs a 6,000 hr CF) i picked a 1 to 3 ratio of whites to blues because i am supplementing the two 150w MH. it seems to give the perfect amount of blue to make every coral appear neon!
the only guidelines i can think of are example post from google search (diy saltwater led lighting) from what i have researched you need about 3/4 high power 3w cree xr-e leds or equivilant per gallon minimun. (so 75 3w LED per 100 gallons) or if you look at the spec sheets of the leds you are planing to use you can calculate that you would need 75 to 100 lumens of LED light per gallon.
a custom build is alot of fun and very satisfiying.
 
mastertech

mastertech

Member
holy crap i think i burned my kryptonite candy cane and neon green favia.
moving them to a lower section in the tank... sad :(
 
number1gsxxr

number1gsxxr

Member
Mastertech, thanks for the info!

You might consider placing some window screen under the light until corals adjust, if the LEDs are that much brighter.
According to your formula I'd need roughly 56 minimum of the Cree LEDs for my 75-gallon tank? Looking at one of the 48" Solaris LED units I noticed that it has 4 seperate panels of 25 LEDs each, or a total of 100 LEDs. I'm assuming it's because they are not as powerful as the Cree LEDs? Also the LEDs are not evenly spaced across the fixture. What do you think of the pattern I came up with? Try to ignore the bad Paint drawing.
 
mastertech

mastertech

Member
Originally Posted by number1Gsxxr
http:///forum/post/3203184
Mastertech, thanks for the info!

You might consider placing some window screen under the light until corals adjust, if the LEDs are that much brighter.
According to your formula I'd need roughly 56 minimum of the Cree LEDs for my 75-gallon tank? Looking at one of the 48" Solaris LED units I noticed that it has 4 seperate panels of 25 LEDs each, or a total of 100 LEDs. I'm assuming it's because they are not as powerful as the Cree LEDs? Also the LEDs are not evenly spaced across the fixture. What do you think of the pattern I came up with? Try to ignore the bad Paint drawing.
i think that is alot of white leds. they (white) by nature of design and composition will put out more lumens per watt than the royal blues will. i think you will need less whites and more blues. (like 1 to 3 or 3 to 8 white to blue ratio)
you will also want to design it so the whites and blues are on separate circuits so that you can control the intensity seperatly. you will also want potentally two or three differant power supplies so that you can place sections of the light on timers that will give you more control over the schedule. (sorry for any misspellings. im very tired, just set up a QT for the new 5" powder brown tang that is stunning and i only paid $18.99 at the LFS new year sale!!!)
 
number1gsxxr

number1gsxxr

Member
Congrats on the Tang. All your points are good. I'll have to tweak my design a bit. I've been trying to research it but I keep finding small nano LED builds or builds where people are using LEDs for just moon lights. I don't think too many people are using them for their main source of light yet.
I really like the 'set it and forget it' idea of the LEDs. Not having to test or remember when to replace bulbs would be great. It really seems like the longterm savings offset the upfront cost.
 
king_neptune

king_neptune

Active Member
where do you go to learn how to wire all this in? I am a simpleton when it comes to understanding this, but Id like to try it out.
 
wangotango

wangotango

Active Member
Originally Posted by King_Neptune
http:///forum/post/3203816
where do you go to learn how to wire all this in? I am a simpleton when it comes to understanding this, but Id like to try it out.
There are a bazillion threads on that other "big forum" and the other big forum that specializes with "nano tanks"

-Justin
 
mastertech

mastertech

Member
ok results are in. this may be interesting.
first off what is installed.
one 96w CF Actinic
18 LEDs, all Cree xr-e (12 royal blue and 6 white)
six 40 degree lenses on the outer most LED's
six 80 degree lenses on the next to outer most lenses and
six without lenses in the middle of the tank.
two double end 10k 150w MH (all coralife)
the readings above the water are interesting (4 inches under the lamp)
HM - 3000 par maxed the meter?
CF - 500 par
LED - 1800 par with 40 degree lenses on royal blue
LED - 2100 par with 40 degree lenses on white
LED - 1300 par with 80 degree lenses on royal blue
LED - 1500 par with 80 degree lenses on white
LED - 1000 par with no lens white
LED - 900 par with no lens royal blue
i also took readings with the top water still and agitated those readings are also interesting. it seems as if you would get larger readings with the water still but i found the opposite (of course the sample rate of the meter may affect the perceived readings) readings seemed to be 10-20% less with water still (refraction of light increased intensity from time to time?)
the differance in par from the CF to the LED conversion is large.
under water readings of the CF (8 inchs from lamp) were about 60 par
under water readings of the LEDs (8 inches) with 40 degree lenses 500-600 par
under water reading of the LEDs (8 inches) with 80 degree lenses 400-500 par
under water reading of the LEDs (8 inches) with no lenses 200-300 par
all of these readings in the pic are on the rock or shelf or cave ect. i hope its easy to read the location of the reading. the CF is in the rear of the tank and the LEDs are in the frt of the tank.
notice the upper rear measurements are "250." That # is from the CF and MH lamps.
notice the upper right/front measurement "680" on top of that SPS. that is from the MH and LEDs with 40 degree lens spotlighting that SPS.
 
mastertech

mastertech

Member
lots of questions about LED lighting and being posted. bumping this post because i have provided alot of information that could answer most of the questions that people are asking.
 
stdreb27

stdreb27

Active Member
This is cool,I might have missed something, I'm curious.
So you are using the power supply that was driving the PC bulbs? I'm wondering was there a power usage drop.
Did you measure the lighting with the old bulbs?
 
swimmer4uus

swimmer4uus

Member
Originally Posted by mastertech
http:///forum/post/3227092
lots of questions about LED lighting and being posted. bumping this post because i have provided alot of information that could answer most of the questions that people are asking.
Yes, very good writeup if anyone actually searches instead of randomly posting questions
(yes I do it sometimes too, but I try to stay away from it without SOME searching)
 
mastertech

mastertech

Member
Originally Posted by stdreb27
http:///forum/post/3227104
This is cool,I might have missed something, I'm curious.
So you are using the power supply that was driving the PC bulbs? I'm wondering was there a power usage drop.
Did you measure the lighting with the old bulbs?
it is a new power supply. the CF is powered by 120 ac to a ballast.
the LEDs are powered by a 120v ac to 24v dc converter.
the 96w CF was replaced by 54w of leds with three times the PAR.
old CF ratings are covered in the post with the PAR readings. you can see i still have one in the hood.
our local aquarium org. is passing around a PAR meter and we have lots of differant tanks with differant fixtures, bulbs, ballast, k ratings, ect. (even three 24 inch skylights over a tank) we are currently colaberating all the PAR readings and i will try to post some more readings with various lamps as soon as they become avail.
 
stdreb27

stdreb27

Active Member
Originally Posted by mastertech
http:///forum/post/3227156
it is a new power supply. the CF is powered by 120 ac to a ballast.
the LEDs are powered by a 120v ac to 24v dc converter.
the 96w CF was replaced by 54w of leds with three times the PAR.
old CF ratings are covered in the post with the PAR readings. you can see i still have one in the hood.
our local aquarium org. is passing around a PAR meter and we have lots of differant tanks with differant fixtures, bulbs, ballast, k ratings, ect. (even three 24 inch skylights over a tank) we are currently colaberating all the PAR readings and i will try to post some more readings with various lamps as soon as they become avail.
So what would it have taken to completely switch over?
 
mastertech

mastertech

Member
I guess the answer to that is more money.
i am going to convert the other CF to led in the near future. that would leave me with at least 36 LEDs and 2 150w MH. this would provide at least 800 par over the top 12 inches of water if i turned everything up. to replace the HM with LEDs would cost alot (but worth it)
cree has a new white emitter out, the xp-g. it is about 50% more efficient and output about 300 lumens at 350ma vs the xr-e that output about 100 lumens at 350ma.
it is still a 3w lamp so my est is. to replace one 150w MH i would need about 20 xp-g lamps.
 
stdreb27

stdreb27

Active Member
Originally Posted by mastertech
http:///forum/post/3227272
I guess the answer to that is more money.
i am going to convert the other CF to led in the near future. that would leave me with at least 36 LEDs and 2 150w MH. this would provide at least 800 par over the top 12 inches of water if i turned everything up. to replace the HM with LEDs would cost alot (but worth it)
cree has a new white emitter out, the xp-g. it is about 50% more efficient and output about 300 lumens at 350ma vs the xr-e that output about 100 lumens at 350ma.
it is still a 3w lamp so my est is. to replace one 150w MH i would need about 20 xp-g lamps.
Wouldn't a more accurate conversion be checking the lumens not the wattage?
 
mastertech

mastertech

Member
PAR is more important than lumens when comes to coral life.
PAR-Photosynthetically Active Radiation ~400-700nm
lumens- Luminous flux (human eye perceptive) ~500-650nm
The measurement compairison that is most telling is PAR vs watts.
the PAR vs watts of the CF is a shadow compaired the the PAR vs watts of the LEDs.
the PAR of HM is very high compaired to the watts consumed. but LEDs would still surpass efficency performance and reduce heat in the tank at the same time.
 
reefraff

reefraff

Active Member
Very cool.
Something very important to keep in mind when measuring PAR. The Royal blue and white LED's are supposed to produce about the same amount of PAR according to someone with a Spectrometer which is the most accurate way to read them. The quantum PAR meters under read blue light, especially closer to the violet range, and over read red. I measure PAR just over 300 on a Blue Plus T5 lamp and 345 on a UVL Aquasun which is slightly pink daylight color. A measurement was made using a spectrometer and it turns out the Blue Plus produces more PAR
Sorry for the slight hijack but wanted to make sure the folks knew about that, don't hesitate to go heavy on the blues.
 
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