Tomorrow will be the 1 year mark running this DIY 10 watt multi-chip fixture. It's been working great, no LED burnouts despite the fact that a few of the fans failed and the LEDs are basically no name cheapies. I have replacement fans so not a problem there, but I would probably build it a little differently next time around. There are now slightly larger heatsinks available for 10 watt multi chips that supposedly cool sufficiently without a fan directly attached. I'll probably order a few of them to check it out. I think if I built a top on the fixture and added a couple of larger fans to move air through that, it may work without all the individual mini fans. I have something in mind along the lines of a semicircular piece of wood at each end, then adding thin slats across the top with a slight space between each. This will cover the top nicely while allowing air circulation similar to the open top configuration at present.
Livestock is happy, coral growing & my BTAs have never looked better. In fact they are taking over the tank. I'm still slightly underdriving most of the LEDs, so they should continue to plug away for another year or two no problem. The fixture is likely nearing the point where it will have paid for itself in power savings & not having to buy replacement halides and T5HO lamps. Starting to get the itch for another build though, this time with larger, fewer multi chips. Anyone contemplating a DIY LED fixture should at least consider these multi chips rather than the more common builds using 3 watt Crees etc. They may not be quite as efficient as the Crees or other big name brands, but the price is right & they work fine. They also now come in multi colour arrays on the same chip. Fewer LEDs can be used meaning less wiring & soldering.
