Quote Originally Posted by XSiVE View Post
Hey Rob, low light creatures in a tank that size can probably be lit by something like 18 LEDs without optics..
Ah, there you are sorry I forgot your name but I believe you and I were discussing a fixture for this exact tank about a year ago if I remember correctly!?

Quote Originally Posted by jimsflies View Post
I've got 16 3w crees (9 blues/7 whites) with no optics over my 29 biocube. The PAR measures 650! I currently am only running the LEDs at 20% which is a lot more (220) than my old 150 watt halide was providing (60). For comparison, a 14k 150 watt halide was about 340 when new.

My guess is that a lot of people without access to a PAR meter, smoke their corals under LEDs.

As I mentioned rob, I have the dimmer pieces parts that came with the DIY fixture I bought that you can have. It includes a 12 volt transformer which is used to power the dimming circuit....although as I understand it, a 10 volt is what you really want. Having seen one of these now, I can see how easy they are to put together.
Wow Jim sounds like a great set up. Are you getting good growth? How long of a light acclimation period did you use?
I was thinking of that exact number of LED.
I very much appreciate the offer on the hard goods, Ill have to see if I can weasel a few bucks out of the paycheck to send you for postage!

Quote Originally Posted by dumbderk View Post
Yea for a 15g with those dimensions a heatsink being 22''X8'' would work fine. From Heatsinkusa your looking at around $54 for an 22''X8''. As for the amount of leds if jim is running his bio on 16 leds I am not sure on how many you would need contact rapidled with the dimensions of your tank and tell them you want a 20k look being able to grow anything you would want, or use the old mh wattage per gallon method. Also the closer the leds are together the less they spotlight but with your tank bein the depth and width they are they will probably be spread pretty far apart so no optics will work great.
Optics are one thing that Im not certain I need. As I remember they are used to concentrate the light in to one area more, particularly useful with tanks of greater depth. I will keep the initial set up costs down if I don't, and well they can always be added later right. Maybe after cycle?

Do you think Heatsinkusa will have the appropriate drill, tap and screw set or hopefully rapidled? The thermal paste is just to help dissipate the heat not actually secure the LED to the sink?

---------- Post added at 06:28 PM ---------- Previous post was at 06:26 PM ----------

By the way is the transformer the same as an AC/DC power supply from a computer? I used one off my old computer to make a power supply to my RC car Lipo charger....... been racing a little since I got out of salt!