OK:headwalls: I have read most all the posts here and am still so confused because alot of this I do NOT understand. I have a 75 gal 48x18x20ish reef tank. All I want to do is light this baby up to where the corals will be happy and still pleaseing to the eye. what will I need? I do not have a controller so I will need to dime the light mannually with pots or somthing and put them on timmers for now. I need:
What multichip LED and wattage
What driver(s)
Lens
Heatsinks
Ect?
Just want to have a good light source and get rid of my t-5 and MH setup
Quick question for the experts... My tank is a 110 Tall, 48" X 18" X 30", and I have two 100 watt chips and a number of 3 watt chips to supplement them. I am going to be designing my fixture here soon and was wondering what you guys would recommend for spacing?
Would it be better to build a more compact fixture for a single light source type look? Similar to running a single high wattage halide...
Or should I spread the fixture over a larger foot print to get better spread?
That being said my limiting factor is that I only have about 12" above the water to place the fixture... I have a full machine shop and can make anything so I was even thinking about making the chip mounting angle adjustable if that would help?
Any help would be greatly appreciated!
Thanks,
Jeremy
A long narrow tank such as yours does not lend itself well to multichips as most of the light will spill over the front and back. The 90˚ lenses cover a 30" x 30" footprint and the 120˚ lenses cover 36" x 36" when using 50 or 100w multichips.
I don't have any experience with 10w chips, but they may be a good fit for your footprint. Certainly a standard 3w array fixture will do the job, and many are the same price or cheaper than DIY; however, if you want the DIY experience, then copy someone else's design directly. Preferably someone with the same narrow (18") tank that isn't very deep (20"). Your dimensions are pretty much the same as two nano tanks, so that may be a good place to look for DIY layouts or complete fixtures.
I think TropTrea's recommendation of 175w is about right.
You may even consider 3 x Par 38 bulbs and call it a day.
Here are some better pics of the multichips as promised. I hope these aren't deemed as commercial in nature, as I am only trying to illustrate how 400w of LED can replace 1200w of metal halide and T5. I didn't post any shots that show livestock to keep it within the RC guidelines.
The multichips provide the same PAR as the outgoing 250w MH (300 in the centre and 280 at the outer edges using the 120˚ lenses with the fixtures 2' above the water surface. The 90˚ lenses provide 400 PAR at the centre and 200 at the outer margins (18" out from centre).
The 20K multichips are a lot bluer than the 14k Phoenix, and even the generic 20k MH we had in some fixtures, so the PAR is likely higher with the LEDs considering the limitations of quantum meters and blue light.
The MH fixtures were heavy, extremely hot, and expensive to maintain. The new LEDs look sharp and give the same shadowing/shimmer as the MH. Water temperatures are way down and corals look much nicer.
Here's a shot of the old metal halides which served us well for the past 9 months.
![]()
Here is the same angle with the LEDs. You can see how the LEDs focus the light in the tank, rather than on the floors, walls and ceiling. The LEDs also provide an awesome light show on the ceilingThe PAR at the top rim of the tank was 200 with the MH and only 10 with the multichips, so algae growth is greatly reduced on the glass, yet the corals along the outer margins still get 200 PAR.
![]()
![]()
![]()
Nice Mr.Wilson what type of enclosure did you use
Sent from my SPH-L710 using Tapatalk 2
I will double check the power supply.Thanks for the help
Thanks for the reply Mr. Wilson. I may just go ahead and build a 3w led set up and be done with it...Thanks again
Mr Wilson, I like your set up...looks like you could eat off your floor. I wish we had shops so clean around my area. On your fixture, is it a single point light source chip, or do you have additional chips around your main chip.---Rick
Mr Wilson, I like your set up...looks like you could eat off your floor.