Diy led questions

[DarinSchmidt]

and each heatsink is going to be 34" long or combined?

[Learning_The_Hard_Way]

I have XPG and XRE mixed and they are 2.5 apart and it worked out well.  I have 65 deg optics.  The bigger the heat sink the more surface area to dispurse the heat.  I could not belive the difference a fan made in the cooling as I was considering not having one in the beggining get a good one that is low noise.

[DarinSchmidt]

Likewise hardway. I made a little test unit runing at 350mA a while back (both units in the pic below were test units), it got warm, but nothing to be concerned with, but when ramped up to around 700mA, they got really hot. Wouldnt burn you, but enough to make me concerned about the life of the LEDs.



here is an equation that i made to help easily get you in the ballpark of what you "should" have as far as lighting so that you have a good even spread, but of course optics and distance above water surface isn't factored into this yet.

FO tanks dont require as much lighting.

-------------------------------------------------------------------------
W= (total width) - (including exterior edge measurement)
L= length of tank - (including exterior edge measurement)

(((L-8)/2).6)=a = # of columns
(W-4)/2=b = # of rows
NOTE: round a and b up to the nearest unit
a*b= # of LEDs
a=rows
b=columns
--------------------------------------------------------------------------

so for example, if you have a 55g tank, 48x13:

x= distance you want between each LED
x in this case is 2
(((48-8)/x).6)= 12
(13-4)/x=4.5 = 5

the above equation requires 2 heatsinks placed evently between the braces of the tank

12*4.5=54 median
12*4=48 min
12*5=60 max


then from there you can figure out how you want to place the LEDs.

Just remember, this is a ballpark figure. I had done some testing with a couple tanks and this seems to work rather well for me.

[Cole Harlow]

I have a 210 gallon tank

[DarinSchmidt]

-------------------------------------------------------------------------
W= (total width) - (including exterior edge measurement)
L= length of tank - (including exterior edge measurement)

(((L-8)/2).6)=a = # of columns
(W-4)/2=b = # of rows
NOTE: round a and b up to the nearest unit
a*b= # of LEDs
a=rows
b=columns
--------------------------------------------------------------------------

so for example, if you have a 55g tank, 48x13:

x= distance you want between each LED
x in this case is 2 incorrect, copied this from an old thread i was working this out on, it's supposed to always be 2

(((48-8)/2).6)= 12
(13-4)/2=4.5 = 5

I believe your tank is 74x24?

if so then its 20 leds per row, 10 per column. Thats MAX. for best LED spread 1" above tank surface, so you can go lower than this if you want. 200 LEDs, min would be 120 LEDs min at 1" above tank surface. I have to still fine tune that equation as it's only partial. But, doing 7x LEDs will be fine with some optics and if lifted high enough IF spread is something you are concerned with, otherwise you will just see where the light beam focal points start to diminish which to some isnt that big of a deal since its near the edge of the tank.

I'm just going to take a wild guess that if you can get them 4-6" above water level, you shouldnt have any spread issues. I have done the same with mine, 128 LEDs over my 300 (96x27" tank). My LEDs are also 2.5" apart. But i do have a little "fade" near the front of my tank because i dont have them lifted high enough.

[DarinSchmidt]

i'll get back to you on this once i get home. I'll draw a diagram and redo my equation including the height from the sandbed to the leds.

[Cole Harlow]

My tank is 84 inchs by 24 inches

[DarinSchmidt]

ok, just to keep things basic.

you have a 34x8.5 heatsink. palce them 2" on center thats 16x4=64 leds. any more than that per heatsink and you will be reducing your LEDs a lot to not burn your corals.

[Wall_Tank]

To plan or expect 100% even light levels over the entire 72x24 foot print is bit unrealistc.  And 1" off of water is not anything to even recommend.    12" above the water surface at a minimum.   There is no reason to mount LED's low.   200 3 watt LEDs is quite a bit too many.

Is this a standard plastic framed 210?  If you have the plastic braces across the top, you need to avoid putting light directly over top, otherwise you will get nasty shadows.

[DarinSchmidt]

To plan or expect 100% even light levels over the entire 72x24 foot print is bit unrealistc.  And 1" off of water is not anything to even recommend.    12" above the water surface at a minimum.   There is no reason to mount LED's low.   200 3 watt LEDs is quite a bit too many.

Is this a standard plastic framed 210?  If you have the plastic braces across the top, you need to avoid putting light directly over top, otherwise you will get nasty shadows.

I wasn't recommending 1". I stated mine were higher. Most tank lights sit 1-6" above the water. Unless you have a canopy or a hanging unit. Have you done any tests with the 3w leds? I'd like to hear what you have to share.

[kattz]

While you're at it, use three 18" heatsinks; put your LED's at least 12" above the water - mine are 15" from splashguard to water's surface.

[Cole Harlow]

While you're at it, use three 18" heatsinks; put your LED's at least 12" above the water - mine are 15" from splashguard to water's surface.

i couldnt use 3 heatsink without one janging rightt over the glass brace in the middle of the tank

[DarinSchmidt]

If its glass o wouldn't worry about it. I do agree with using 3 HeatsinkUSA though

[Cole Harlow]

To plan or expect 100% even light levels over the entire 72x24 foot print is bit unrealistc.  And 1" off of water is not anything to even recommend.    12" above the water surface at a minimum.   There is no reason to mount LED's low.   200 3 watt LEDs is quite a bit too many.

Is this a standard plastic framed 210?  If you have the plastic braces across the top, you need to avoid putting light directly over top, otherwise you will get nasty shadows.

Its got a plastic frame but a glass  brace its not a standerd 210 its 84 by 24 by 24inches

[DarinSchmidt]

you plan on using optics correct?

[Cole Harlow]

While you're at it, use three 18" heatsinks; put your LED's at least 12" above the water - mine are 15" from splashguard to water's surface.

I was thinking about this and was wondering if i could do 3 heatsinks each with 36 leds plus the reds and plain blues to bring out the corals collars. Im probly going to use 60 degree optics rapid led has nothing bigger for xp. If i used the idea above approximattly how many nle /red leds should i have per heatsink, i also want to make sure that the lig would make it throught the glass brace in the center of the tank

[DarinSchmidt]

if you did your idea with the 34" heatsinks to avoid passing through the center brace it would look like this to scale:



its not a bad idea to do it this way though.

36" (including the 12" height above water line with 60 degree optics) gives you a 62" diameter focal point. Which is more than enough at sandbed level.
at 30" above sandbed it gives you 52" diameter focal point.

this model uses 136 LEDs

[Learning_The_Hard_Way]

Cole call Mike at Rapid LED and he sometimes can let you know if they have any coming or on the way.  I got some greater than 60 by asking.

[Wall_Tank]

Its got a plastic frame but a glass  brace its not a standerd 210 its 84 by 24 by 24inches

I run 35 3 watt XR-E's per fixture...  this is a std 90 gallon.   Maintain mostly SPS, and a few LPS in the darker corners.

The glass brace is probably not a problem, but I would avoid it.    Your going to need different intensities in your tank.  Not everything likes super bright.   So design in some darker areas and put the appropriate corals there.

I'm not sure I remember what you plan to keep in the tank?   How bright do you want it?   But I would probably use 30" long heatsinks for ease of mounting, but may not use the same LED spacing across the whole heat sink.

[DarinSchmidt]

this is what it looks like with 3 units 18" using 108 LEDs.



All these diagrams are based off of LEDs being 2" on center so however many LEDs you actually use based on the PSU will determine their placement and how many you use.

[Cole Harlow]

I run 35 3 watt XR-E's per fixture...  this is a std 90 gallon.   Maintain mostly SPS, and a few LPS in the darker corners.

The glass brace is probably not a problem, but I would avoid it.    Your going to need different intensities in your tank.  Not everything likes super bright.   So design in some darker areas and put the appropriate corals there.

I'm not sure I remember what you plan to keep in the tank?   How bright do you want it?   But I would probably use 30" long heatsinks for ease of mounting, but may not use the same LED spacing across the whole heat sink.

how many fixtures do you have? Id like to keep mainly lps and sps in my tank

[Wall_Tank]

2,  I will add a 3rd fixture when I upgrade to my 180

[DarinSchmidt]

i have a tank thats 96x27, 4 28LED units, i have LPS, SPS and softies

[Cole Harlow]

Ok just thought of a problem since i have 36 leds and three drivers how do i put the leds on a dimmer without having to put both blue and whites on the same driver could i alternate the blues and whites . Im trying to get a 15k to 20 k look on my tank should in just get 24 nlues and 12 whites ?

[Learning_The_Hard_Way]

Thats a problem that you can work around, your going to have to be more creative in your placement and run more wires.  I would just get another driver and run each on a seperate dimmer.  But.... if you want you can put blues on one, whites on one, and blues and whites sprinkled throughout on one and run it with the white dimmer so you can have a true blue led moon look.