Just wanted to share my LED build.
I used black 20mm anodized aluminum for my heat sink, and purchased the LEDs and associated accessories from ledgroupbuy.
8 x CW XML2 (@ 1000ma)
8 x WW XML2 (@ 1000ma)
4 x OCW (RGB) (@ 500ma)
I chose the XML2 as they are really efficient, and I could get away running them without cooling or fan noise. I'm running them only at 1amp (3 watts). I can always upgrade the driver and power supply and go as high as 10 watts if ever necessary. (And of course add cooling)
My tank is a 46g bowfront which has a glass lid that I intend on using, so I did not need to add a shield to protect the wiring or LEDs. However, because of the hinge on the lid, I was limited to keeping the fixture narrow and went with a single row of LEDs spaced approx 2" apart.
I left a gap in the middle of the fixture to account for the tank bracing. Due to the bow, I used 60 degree optics on the 2 LEDs closest to the edge, and 80 degree optics on the other LEDS. The OCW have built-in 90 degree optics. This helped fill out the bow in front without wasting as much light on the sides of the tank where its narrower.
The image below shows only 50% of the optic angle as most of the LED light is within that zone.
Here is the unit after wiring it up.
I tapped the ends of the extrusion and cut out black acrylic for the end caps. I might cut some out that are slightly larger as some of the aluminum peaks through these.
I tapped the extrusions to accept 4-40 screws so that the LEDs could be changed out if necessary. Thermal compound was used between the LED and the extrusion. Lenses were attached using a hot-glue gun.
Here is how the unit sits on the tank - and you can see the hinge on the glass lid I mentioned earlier.
Here are the drivers and power supply (48v). I went with 5 channels total, one for the CW and WW, and one each for the RGB on the OCW board as I wired them individually for better colour control.
The box was laser cut and then stained. Connectors were added to go to the LEDs, and another for the PWM control which are temporarily wired to an Arduino UNO until I sort out how I'm going to control everything more permanently.
And finally, a shot of them in action!
According to hoppy's awesome calculator (https://www.plantedtank.net/forums/sh...d.php?t=168999
), using an average of 371 lumens (412 cw, 330ww) - I get ~54 PAR where the 80 degree lenses are at the substrate, higher at the edges.