This build is designed for a "Full Spectrum" dimmable LED fixture for a mixed reef 40 breeder aquarium. This fixture helps achieve the different wavelengths utilized by various coral. This instructable will not go into detail about different types of reef lighting, or the benefits of full spectrum since there is a lot of information on the internet already discussing these topics. It is purely a building guide.

This fixture does not require fans; therefore is is completely quiet.
This fixture can be controlled manually or with an aruino.

This project requires soldering know-how and deals with electricity. Caution should be used at all times to avoid being shocked or burned.

Step 1: Materials

Everything for the fixture was purchased from two sites:
www.rapidled.com & www.stevesleds.com/

The attached Excel file is a breakdown of items purchased, site, and price.

Optics are not on the list because they are optional, but 80° optics were used on all Royal Blue and Neutral White LEDs. The optics help the light being emited become more directional, but could cause a "disco effect" if not careful.

Lux DIY LEDs.xlsx
Download

Step 2: Layout

When drawing the guidelines, it's best to use a yard stick. A 12" ruler will work, but it's not long enough to go across the entire heat sink. Use a pencil for the marks, which can be easily erased if an error is made and once completed.

On one of the 6" sides of the heat sink, measure and mark 1 7/8" from each corner and 3". There should be 3 marks (reference picture 1). Do the exact same thing for the other short side. Draw 3 straight horizontal lines connecting the marks across the entire heat sink. These will be your horizontal guidelines.

Starting from one of the 6" sized of the heat sink, measure and mark 2 1/2". Draw a vertical line at this mark intersecting the 3 horizontal lines created prior. Continue measuring and marking every 2 1/2" until you have 7 vertical lines. A post card is small enough to help draw internal guide lines.

NOTE: DO NOT PERMANENTLY MOUNT LEDs ON HEAT SINK PRIOR TO SOLDERING

Temporarily place the LED's on the face of the heat sink matching the drawing. This allows the proper length of wire to be cut and soldered before permanently placing the LEDs on the heat sink.
The idea is to have four circular bunches of LEDs. Each bunch will have one 3-UP, two neutral white, and four royal blue LEDs. Each bunch will be segregated with one true violet.

Using the layout (reference picture 1) start with the 3-UP LEDs. There are four 3-Up LED, and they will be placed on the center horizontal line and spread evenly.The first 3-UP will be at the 3" & left most 2 1/2" intersection. Following horizontally on the 3" guide line, place another 3-UP every 5" (skip every other 2 1/2" vertical guideline).
After the 3-UP are placed, place the three True Violet LEDs on the remaining 3" & 2 1/2" intersections.
Using your best judgment and with the help of the 3" horizontal guide line, place one white LED on the left and right of each 3-UP. Try to center these LEDs between the 3-UP and True Violet LEDs.
Eight royal blues will be placed on each 1 7/8" line. Spread them evenly (using best judgment) to complete each circular bunch. Make sure all LEDs are rotated identically for cleaner wiring.

Step 3: Wiring the LEDs

Once satisfied with the layout, start cutting wire and soldering the LEDs together. There will be three separate circuits that will allow you to control each color group. This is done for two reasons: more control on color output and a single driver can't support all the LEDs. For the maximum number of LEDs, calculate the forward voltage of each LED and divide the forward voltage of the driver.

Example: The Mean Well 48D Driver has a forward voltage of 48V, and the royal blue LEDs have a forward voltage of 3.0V. Dividing shows that the driver will allow 16 royal blue LEDs. 48 / 3 = 16.

Since there are only eight white LEDs on the second circuit, I decided to add two royal blue LEDs to it.

Circuit 1 = 14 RB = 14 LEDs (42V)
Circuit 2 = 8 NW, 2 RB = 10 LEDs (30V)
Circuit 3 = 4x3-UP (Blue, Red, Cyan), 3 True Violet = 15 LEDs (44.66V)

When soldering the LEDs, don't rest them on the heat sink since its purpose is to dissipate heat. On the first LED of each circuit, use a red or white wire to connect to the positive side of the LED. Make sure this wire is long enough to connect to the driver and it could always be cut shorter later. The LEDs will be soldered in series (negative to positive) and these will be indicated on the LEDs with a - and +. At the end of the circuit use a black wire to connect to the negative side of the last LED. Make sure this wire is long enough to connect to the driver and it could always be cut shorter later.

Circuit 1:
Using the first wiring diagram, connect 14 royal blue LEDs in series. Do not connect the top left or bottom right (indicated on picture 1) royal blue LED because this will be connected to the circuit 2. Once soldered you can either mount the circuit to the heat sink with the thermal paste, or connect the circuit to the driver to ensure they work properly. If you do decide to test them first, be careful not to leave them on too long because they will get hot.

Circuit 2:
Using the second wiring diagram, connect 8 neutral white and the remaining 2 royal blue LEDs in series (indicated on picture 2). Start with the white LED furthest right, and connect every other white LED ensuring you connect the top left royal blue LED. Loop back around and connect the white LEDs that were skipped and the bottom right royal blue LED. The idea is to minimize how much loose wire there will be. Again you can either mount the circuit to the heat sink with the thermal paste, or connect the circuit to the driver to ensure they work properly. If you do decide to test them first, be careful not to leave them on too long because they will get hot.

Circuit 3:
Using the third wiring diagram, connect 4 3-UP's and 3 true violets in series (indicated on picture 3). Start with the 3-UP and skip every true violet. Loop back around and connect the true violets. Once again you can either mount the circuit to the heat sink with the thermal paste, or connect the circuit to the driver to ensure they work properly. If you do decide to test them first, be careful not to leave them on too long because they will get hot.

Step 4: Potentiometers and Power

The drivers can accept a 0-10V signal. Using an AC adapter of 10V and three 10k potentiometers allows you to vary the voltage between 0-10V, thus dimming the drivers. The higher the voltage, the brighter the LEDs. The attached wiring diagram should be everything you need to connect the potentiometers to the drivers and power.

The three drivers can be connected in parallel to one 120V AC power cord.

DO NOT SOLDER THE LED WIRE TO THE DRIVER WIRE YET.

The red and black wires on the driver will connect to the red and black wires from the LEDs (red-to-red & black-to-black). Each driver will connect to its own circuit.

Adjusting SVR2 Tutorial:
The SVR2 located on the Mean Well 48D will need to be adjusted to provide the proper amps to the LEDs. RapidLED has created a youtube tutorial on adjusting the SVR2. Instead of explaining it, here is the link to the tutorial.

THE SVR2 MUST BE CONFIGURED CORRECTLY TO PREVENT DAMAGE AND ALLOW OPTIMUM PERFORMANCE.

Step 5: Complete

At this point the LEDs should function completely and are ready for mounting. There are many ways to mount these fixtures, and you can even buy a mounting kit from RapidLED. These LEDs are strong and should be at least 10" above your aquarium. I started these LEDs around 35-40% on day one, and increased the intensity over a few weeks to help prevent coral bleaching.

Wire looms were used to bundle the wires neatly.

The pictures show my tank with the different circuits on individually, and with all the circuits on.

The first picture is royal blue LEDs.
The second is neutral white LEDs.
The third is 3-UPs and violet LEDs.
The fourth is ALL LEDs on.