Help with lighting please

[Salinero831]

Hello all i am new to the hobby and i would like to start a 20g nano tank the tank dimensions are 12-1/2"L x 30-1/4"W x 13"H. i have 20 3w leds (10 royal Blue-10 white 15k) 2 dimmable drivers. can someone recommend the size of the heatsink i should use? is this enough wattage to keep corals? please any suggestions would be greatly appreciated

[Salinero831]

Somebody help

[Vince272992]

No probably not, so I would keep ur fixture for some extra light or I would sell it and rtey and get a real fixture such as radions, or some other LED fixture, if u don't want LEDs there's also T5s that are pretty cheap and good for a reef and then there's halides which are also very good

[Salinero831]

but i have everything i need except for the heatsink

[SoLiD]

I think that you should be fine as long as you put it together properly. With only 13 inches of height I would forego any type of lens because you'll probably bleach out anything underneath the LED light. You should be able to grow any type of coral, granted that you have some good LED pucks to begin with. You might want to take out some whites because they can be over powering. 20 is a great number, but it will be hard to balance it out. You might try 19 or 21. Also might want to throw in some Blue LED's in the mix because when you mix Blue and Royal Blue they look awesome.

Here is a nice LED lay out I came up with for you.
W=White
B= Blue
R= Royal Blue

-R-W-B-W-R-W-B-
()-R-W-R-W-R-()
-B-W-R-W-B-W-R-

Check these guys out too for some ideas.
http://www.rapidled.com/

[Merrell056]

You'd probably be fine with only 12 LEDs (which would only need 1 driver assuming you have meanwells). You can use U-Channel aluminum from Home depot if you want to go cheap but you can also pick up a 12" heatsink from rapid led.

20 3w LED is a LOT of light for a 20 gallon.

[Salinero831]

Thank you all for your help the tank I ended up buying is 24L13W16H
SOLID will your diagram work on a 9x6 heatsink
Merell056 are you sure 12 leds are enough I was planning on using 24 to 36 on dimmable meanwell drivers

[SoLiD]

On a 9X6??? Probably not. You'd be lucky to get 12 on there I think. Those 12 might be enough because it is a smaller tank, but I'd probably recommend you buying a bigger heat sink to fit the 24 you were talking about. Heat is the killer of LED's. When I first saw 20 3W LED's on a 20 gallon tall I saw nothing wrong. Now I think that might be a little much... And This is coming from someone who tends to overdo everything. Oh well it's your reef. It's your decision... Live Dangerously..

Check out the lights on my 40 Gallon Breeder... Some Say It's Rediculous...

[Salinero831]

your tank is awesome!!! do you think a 3.5"x20" would provide adequate light distribution using 24 leds?

[SoLiD]

Nope. Get the Drilled/tapped 6" x 20" Black Anodized Aluminum Heat Sink. It will give you the best coverage with the fewest LEDs. It's only $55

http://www.rapidled.com/drilled-tapp...num-heat-sink/

[Salinero831]

awesome, i looked into them they are on B/O as soon as they have them in stock i will order one. i appreciate the help

[zoafarm]

1. Will 20 3w leds be enough light? Yes, and to be honest...it will be too much. You didn't tell us much about the type of LEDs. However, I'm running 48 Cree LEDs without lens (36 Royal Blue & 12 Cool White) over a 72 gal Bowfront (48"x18"x22"), and they had to be dimmed. So, I tend to agree with Merrell056. 12 LEDs over a 20 gal would probably be fine; however, you are using dimmable drivers and the LEDs can be turned down.

2. As to the combination of 10 blue and 10 white. I think you might find you have too many whites. Most people are using 2:1 or 3:1 ratio of Blues:Whites. But again, you have dimmable drivers.......

3. As for the heatsink, Rapidled has a couple that would work:

http://www.rapidled.com/4-25-x-16-aluminum-heat-sink/
http://www.rapidled.com/4-25-x-23-aluminum-heat-sink/

18 LEDs will comfortably fit on the 16" heatsink OR 24 LEDs should fit comfortably on the 23" heatsink

You could also use aluminum U-channel. Some people use the thin stuff you can buy at somewhere like Lowes or Home Depot. I went to a welding shop and bought 1 1/2" wide 1/8" thick U-Channel. Whatever choice you make, a small computer fan over the top of the heatsink will help with any heat and extend the life of your LEDs.

4. Light distribution. Without lens (which is what I would recommend for your tank) the LEDs spread out approximately 120 degrees. So, with your LEDs 8 to 10 inches above your tank, everything should get light.

Here is my tank under the 48 LEDs running at approximately 60% of full power:

[Somker]

so leds do seam to work. are you running halide as well?

[Salinero831]

Zoafarm your tank looks great! do you think doing 2:1 will work out good also you think a 6x20 is a good size, also what should i do about moonlights?

[chrisfont23]

I run Ecoxotic LEDs on my tank. They absolutely work. Same sentiments as zoafarm pointed out. I have about a 3 to 1 ratio of white to blue and they are running at about 75%. I have 6 fixtures 12k/453nm and two magenta/blue stunner strips.

Here is a shot or two under the LEDs (last one under blue / magenta stunners)

[Salinero831]

chrisfont your tank looks good just to be clear your doing 3w to 1rb?

[chrisfont23]

Here's the light: http://www.ecoxotic.com/panorama-pro-module.html/

[zoafarm]

somker,

just LEDs with no other supplement lights. They run on a 12 hr cycle with 45 mins on both sides being sunrise and sunset.

Salinero831,

2:1 (2rb:1cw) would be fine. I don't have moonlights, but they are beautiful...my next addition. On a 20 gal, you could do 2 moonlights for very little cost.

http://www.rapidled.com/moonlight-kits/

[tylork92]

Wow these tanks look absolutely amazing. What would y'all recommend for a 37g?

[Salinero831]

zoafarm,
how much did you spend on the u-channel? if you dont mind me asking

[Somker]

WOW is all i can say. i cant believe how far lighting has come. my last tank was T8s and T5s, t5s were just being introduced its been a while since i had one. now there every were and leds are just coming out. i cant believe the quality. and the tanks are just stunning.

[zoafarm]

Salinero831,
I bought 16 feet, cut in 4 equal pieces (approx. 48" each). It been a while, but I think is was about $35 +/- a couple dollars.