opinion on LED retrofit

[Bobbofin]

Considering going to LEDs instead of metal halide and actinics on my 60 cube. Considering this retrofit kit: http://www.rapidled.com/servlet/the-23/24-Premium-LED-Do-dsh-It-dsh-Yourself/Detail The eliminates driver the guess work of pucks, resistors and power supplies. Plan on gutting my Current 15" x 13" HQI pendant and re-use the housing, fan and timers.
I have a couple questions:

• Is 24 CREE 3 watt LEDs on a 24" x 24" x 24" acan, lps tank enough?
• In regards to color is 12 whites & 12 blues going to be too white. Aquaillumination have 16 blues and 8 whites. I'm looking for a 15k-20kk looking like I have now.

My calulations show a significant savings, $150 a year on electricity, $200yearly for the replacement of halide bulb and actinics every 8 months. Multiply that by the 50,000 hour lifespan of the LEDs the saving are several thousands!

 

[Bobbofin]

Correction: AquaIlluminatons have 16 white and 8 blue.

 

[Cheetos]

24 sounds about right. I would go with 3 rows of 8 LEDs alternating the whites and blues spaced about 2" between leds and 3-4" between rows. 12 whites and 12 blues will give you a round a 14K look maybe a little bluer. 16 whites and 8 blues would be more like a 10K look. Those drivers are not dimmable so you will have to raise the fixture at first to acclimate your corals. Also, you will need a heatsink to mount the LEDs on...this is a must! You can order any size at heatsinkusa.com. The 80 degree optics will give you 150 watt halide levels, 60 degrees would be like 250 watt levels and 40's like 400 watt levels. Keep in mind the lower number on the optic the more concentrated the beam is. If you aren't going to be doing a lot of sps, I wouuld go with the 80's. You can keep sps mid to high in the tank under the 80's. I would consider not using the thermal adhesive to mount them. I prefer to drill and tap the heatsink just in case an LED goes bad and you have to change it. The thermal adhesive is pretty permanent!
HTH!

 

[Bobbofin]

I think I'm going to go with more of a square pattern because I have a 24" x 24" tank, four rows of five and one row of four. I think I'm going to go with 14 blues and 10 whites to get more of a 15k look. If I don't like it I can change out 4 to shift it more to white. And I will take your recommendation on the 80° optics. Thank you!

 

[Cheetos]

A row of 5 won't give you the right coverage on 24". Rule of thumb is 2" between leds!

 

[DoctaQ]

equal blues and whites are supposed to be 14k and you can turn the whites down(maybe) to get a higher color temp, blue leds have equal growing power as whites, and that is the reccomendation.

that being said my build is going to have 4 blues and two whites which is going to be very blue but thats how i want it, having seen different balances

 

[gregsreef26]

Just checked out that website. Great kits, nice prices. Don't mean to hijack your thread but would their 6 led kit be good on a 14gal biocube, or would 12 be necessary?

 

[Bobbofin]

Never done this before but a 6 will probably do it since their 3w each. You'll also need a heat sink from heatsinksusa dot com. Check out nanocustoms dot come, they have ready made kits for cubes.

 

[Cheetos]

Just checked out that website. Great kits, nice prices. Don't mean to hijack your thread but would their 6 led kit be good on a 14gal biocube, or would 12 be necessary?

I would go with 12 on the 14 gal depending on the dimensions. The number of LEDs has to do with coverage not brightness! I'm running 8 on a 2.5 gal.

 

[focus]

No way will this give you the coverage you need. I ran the identical set up on a 28 gallon JBJ and it was fine, but not on a 60. You won't be happy with it. IMO you would need 36 and even that might not be enough.

There is a group buy on maxspect systems on RC and Nano Reef considering you would need really close to 2 kits this might be a better option.

 

[Bobbofin]

No way will this give you the coverage you need. I ran the identical set up on a 28 gallon JBJ and it was fine, but not on a 60. You won't be happy with it. IMO you would need 36 and even that might not be enough.

There is a group buy on maxspect systems on RC and Nano Reef considering you would need really close to 2 kits this might be a better option.

OK, I looked at them. They are about $500 compared to $300 to build it myself. I know I'd have good coverage left to right but what about front to back where my tank is 24" deep?

 

[DoctaQ]

at 24 in you are gonna need some tighter optics, total guess here but id go with 60at least, and the lpc meanwell is no fun, the eln models can dim, which is not only cool but a necessity

 

[Cheetos]

OK, I looked at them. They are about $500 compared to $300 to build it myself. I know I'd have good coverage left to right but what about front to back where my tank is 24" deep?

Is your tank reef ready? Built in overflow that you wouldn't have to light? I still think not being an sps tank that 24 will do. You have to be careful with too tight optics and that number of LEDs....why I suggested 80's.

 

[focus]

OK, I looked at them. They are about $500 compared to $300 to build it myself. I know I'd have good coverage left to right but what about front to back where my tank is 24" deep?

Couldn't tell you the coverage, most likely you would need 2.

If you really wanted to do this get at least 2 kits or piece it together with meanwells that dim. Don't forget the misc costs cooling fans power supplies quality taps and drill bits,proper splash shields etc.

I will tell you this you would never go back to anything else after having leds...

 

[Cheetos]

I will tell you this you would never go back to anything else after having leds...

Agreed!

 

[DoctaQ]

yep.

 

[Muddskipper35]

So next week I am placing my order from here as well. I am ordering the 24 led kit but with dimmable drivers to use on a APEX system. I am also researching UV and red leds to integrate on another driver I have into this system. These guys have GREAT customer service and are more than willing to help you figure out EXACTLY what you need. IMO on a 65 you need at least 36 leds and I would go with the 60 optics if your looking to keep anything on the bottom. Again just my opinion.

Little info on light diffusion from MIKE @ Rapidled.
As for the spread of light, there isn't a spec sheet but you can calculate this using trigonometry. Pretend that the light coming down is one big triangle. Now cut that in half down the middle to make two right triangles. So if you were using a 40 degree lens you'd have a triangle with angles of 20 degrees (found by cutting the large triangle in half), 90 degrees and 70 degrees. If you wanted the depth to be 30", an online triangle calculator (or you can use sin functions) tells you that the base is 10.92". Since this triangle was cut in half you'd have to multiply by 2 and your spread would be 21.84" at a depth of 30". Hope that made sense.

You'll be abe to figure out the diffusion with 60 and 80 degree optics as well..


By the way this is going on a 34g red sea tank.

 

[DoctaQ]

its not quite that simple
look at this
http://www.nano-reef.com/forums/index.php?showtopic=221433

actual par plots, seems to me the effective spread of 60 deg optics is really only about 20-30 degrees for useable light. the reason being that the optic does not distribute the light perfectly, there is more in the middle.

for instance at 14" 3-4 inches away from center your par is dropping below useful levels a 3-4 inch radius spread indicated only 30-40 degrees output

 

[Muddskipper35]

I agree with your statement but in my case or in the case of alot of smaller tanks or tanks with a fair amount of LEDS the overlap between them will lesson the par value lost.
In my case I am hoping/expecting that the 24 leds with 60 optics over a tank that is 23x15x18 will equal a about +/-300 to 350 MH. I'm not a math wiz or anything so I'm speculating on this. I am looking to come close to equaling what my 400w MH is putting out but with a whiter light.

 

[Bobbofin]

I'm doing the Maxspect group buy on Reef Central and Nano-Reef. I'm getting a G2-400-160W. It cost $510 shipping to my door. I know it's a gamble as far as service goes but my "return on investment" is about 1-1/2 years when I factor in replacement bulbs and electricity.