Quite a number of people have asked for an update an in particular where to source all the hardware.
First things first – where do we stand now with LED hardware?
I have now moved past Cree MC-E LEDs for my setup. They are still being used of course but my latest additions are based around the much better 4x Cree XP-G units. These produce significantly more light per Watt. The downside is that they are in a fixed mount and cannot be directed.
Where to get the current Hardware for UK Builders
The Cree XP-G modules are here: http://www.led-tech.de/en/High-Power-LEDs-Cree/CREE-Solutions/4-x-CREE-XP-G-R5-on-round-PCB-LT-1627_120_117.html
The lenses are also available here: http://www.led-tech.de/en/High-Power-Supply/LEDIL-Optics/CREE-GT4-XP-G-optic-44%C2%B0-LT-1626_106_146.html . They are available in three beam angles as I post. Which you use is dependant upon your setup.
I then mount these to this heat sink: http://uk.rs-online.com/web/search/searchBrowseAction.html?method=searchProducts&searchTerm=158-578
For additional cooling I added a high quality fan – you can substitute for a cheaper variant if you wish: http://www.quietpc.com/gb-en-gbp/products/noctuafans/nf-r8
The power supply is an ELN60-48-D from here: http://www.ecopacpower.com/category.php?catid=12 . The D designates analogue dimming as an option. I use a Profilux aquarium computer to achieve this. I run the LEDs flat out off the controller at about 1.4A. XP-G LEDs should run to 1.5A with enough cooling – hence the addition of the fan. As you can see below they run at a mere 27C – although I will be adding a third set of four to this heatsink. You can only fit two per heatsink so I have sliced a second heatsink in half and will thermally join it to the first.
A Word of Warning
This setup of 12 XP-Gs running at 1.4A produces some serious light that could potentially do harm to both you and tank occupants.
Please be careful to never directly look into the LEDs within the main beam angle.
Always make sure that you have used the correct lens to focus the light into your tank. Some inhabitants would not fare well with too tightly focused lenses with such an intensity. I mount mine well above the display as you can see.This allows me good access and for the light to diffuse over a large area.
Three of these Cree clusters will output 6000 lumens of light @ 1.4A using a total of about 60W of energy. I get 200+ PAR over nearly all of my 9 foot square sand bed (including the MC-E LEDs).
Just two clusters (8 LEDS) plus 11 MC-E modules are currently allowing me to grow Seagrass (even more light demanding than most SPS), Cats and Clams in my current display. Total investment in all the lighting so far is just £360.
The finished product: