McReefer,
I am not sure were you are located but you need to drop by and check out Tanner Electronics over in Carrollton. I go there often for my other hobby of High Power Rocketry and from what I have seen here in this forum I think you will love them. It's a Mom and Pop type electronics store meets Harbor Freight kind of place. You just never know what they are going to have on the shelves.
If you are into electronics then it's the place to be. Not only do they have just about the biggest collection of tubes for sale, they also have the most electronics for building any kind of circuit. Resistors, caps, coils, inductors, fets, and anything else you can think of. But the last time I was there and looking for something to use for the LED lighting I am working on I found a few cases of laptop power supplies still new in the box. He sells them for anywhere from $7.00 to $15.00 each. The nice thing about them vs a computer power supply is first the size. The laptop power supply has the transformer in the middle of the cord so they can be placed anywhere, and unlike the PC power supply, they have that nice hard shell around them. So no bare metal to ground, and no part of the supply is exposed to where water can easily get into them.
Most of the laptop power supplies that I have found supply around 12 to 19VDC at 3.75A which in a perfect world would give you 45 Watts of power @ 12V. If they went up to 19V then you would get 71.25 Watts. Not bad for a small little power supply. Even at 12V you should be able to handle at least 3 of your 10w LEDs. Put in the PWM dimmer in the middle of it and you have a great little LED system for you tank.,
If you need to power a bigger set of lights then instead of laptop power supplies I would suggest you find someone with a printer that has gone bad. We had a big HP multi-use printer here at the house that stopped working. I kept the power supply and I am going to use it to power the LEDs on my 150 once I get done building the stand. It is a 31.5VDC @ 3.1A which gives a whopping 97.65 Watts of power. I am using that power supply for my lights and plan on having three circuits in parallel with somewhere around 6 or 7 three Watt LEDs in each circuit.
I have purchased a bunch of the 3 Watt LEDs from a Chinese manufacture for around .79 cents each. They are 20K (White), 10K (not so white), 410nm UV, 455nm Royal Blue, 465nm more blue, and some 520nm Green. I was thinking about using an Ardruino for the PWM for dimming the LEDs but now I think I'll be checking out the dimmers you have been using. I have also been checking out StevesLEDs and I may get a controller from them to test and check out too.
Tim
