Aquarium Lighting

I somehow came to like the idea of having an aquarium sometime last year. I've had Aquaria before, as a child. Anyway, I like plants, and I like water, the are both sources of tranquillity for me. This aquarium will mostly be about plants, therefore, with a general plan to add fish some time in the future.

So, if I want to grow plants I need a good light source. Also, this aquarium is going to be in my living room. I want the light to flicker and sparkle through the moving water. It turns out this rules out just about every aquarium package you can buy. They either have wimpy LED lights, or fluorescent lighting. The wimpy LED  lights aren't really going to make the plants grow, and the fluorescent lights don't sparkle. I was quite keen on some sort of all in one set-up, that I could tinker with later, but since I can't get what I want, I've got straight to tinkering!

I've bought some Luxeon Rebel LEDs. I'm based on the UK, but they sell direct world wide, and the shipping is reasonable. I bought three of these: Cool White (5650K) Rebel LED

Along with lenses and thermal tape. I used a discarded Xeon low profile passive heat-sink for all three. I was going to drill the heatsink, and screw the led packages in place, for maximum efficiency, but that didn't work out, so I resorted to the fall back of the thermal tape. It'll be a long time before I know if that's good enough - its not like I have the equipment to measure the temperature of the LEDs. The heat sink is a comfortable 40C.

Using the thermal tape makes everything pretty easy - you only need to use conventional soldering. I stuck the LEDs on to the heat sink first to make it a bit less fiddly to do the soldering, but it was then a little hard to get the pads hot enough. I only have a 20W iron, though.

I've created a custom wooden wall lamp to hold the heat sink, and attached it to the wall above where the aquarium will be. I'm quite pleased, but I'm no master craftsman. See what you think:



The lamp hooks onto that block on the wall, so I can get it out the way to work on the aquarium if I want to.

I can't tell if all the LEDs work. I've got a dimmable driver, which I bought in the UK. When I turn it down to minimum, I can look at the LEDs, and one of them isn't working: the V+ most one. When I turn the light up, as in the picture above, it looks like they are all on. Perhaps its the fault of the driver. Anyone know?

For completeness, here's the driver I bought: 20W 700mA AC-DC Dimmable constant current driver along with its matching pot. Hopefully I'll make some sort of 10V controller in the future, to simulate sunset and sunrise.

You will notice there's no aquarium yet, but that will be the subject of a future post.

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