Greg's son here.
I used 42 total LED
All the lights were single emitters.
XT-E Royal Blue (RB) x24
XP-G Neutral White (NW) x14
Slightly more than a 2:1 ratio but a 2:1 will work fine. This will give you a very blue tank. If you want to whiten it up without washing out your colors you can add some red (660nm) and cyan (490nm). This will make the colors in your tank "pop" more and make it look less blue to you without washing out the colors.
Some people go with 1:1 ratios without the red & cyan however I feel this makes the tank look washed out and have no color. With that being said, 2:1 is to blue so offsetting that with the red / cyan to me seemed like the best option. I personally added 2 of each but I wish I had added 3 of each. The difference it made was amazing!
From my research there are 1000 different ways to go with LED
. I find the commonly considered safest bet is what I posted above.
I used inventronics drivers and hooked them up to standard 12v pots for dimmers. 3 drivers 2 running 12RB/1CYAN/1RED and 1 running 14NW.
Inventronics drivers were suggested to me and while I cannot compare them to meanwells (never used them) I can say I am 100% satisfied with the inventronics.
As far as the construction goes, I know nothing about electricity beyond in simple in series circuits. With a little research and patience I was able to build the panel with no problem. However I would say if you aren't comfortable with soldering you get the pre-soldered leds or the solder-less clamps. Its super easy though.
Hope this helps!
as far as optics (reflectors) go it depends on how much water your punching through. I personally wanted SPS
in the top 2/3 of the tank so I needed good penetration.
Optics reflect 80% of the light within the first 50% of the optic so an 80% optic really can be considered more like 40degrees.
8-10 inches above the water on a 18" deep tank I have 80degree optics. If you set your panel really close to the water then you don't need optics.
This has more info on optics http://www.ledgroupbuy.com/pages/Cho...ght-optic.html