DIY LED for 90cm/36 inch 48 gallon tank -FINISHED! Pics/PAR levels on page 2

[IWANNAGOFAST]

Ok, I've been reading all the LED threads while at work and it's time to poop or get off the pot.

I have to replace the 3 bulbs on my 3x39w t5ho fixture soon and with the bulbs costing me about 25 a piece, I figure I might as well go LED and get it over with.

My tank dimensions are 90cm x 45cm x45cm or 36x18x18 inches. Light will be mounted however high it'll have to be to give me 70-75 micromols PAR rating.

I've always tinkered with computers, but never built anything of this magnitude before.

What I've ordered:
30 7000k Steve's LEDs. Half the price of Crees. (I only plan to use 28, but 2 are just in case of mess ups)
http://shop.stevesleds.com/3-watt-Pu...chip-7000K.htm

2 Mean Well LPC-60-1050 drivers
http://www.rapidled.com/servlet/the-...onstant/Detail

Power cords, thermal adhesive and hanging kits.

Total spent so far: 181.28

Still need: heat sink.

I was about to buy a 30x7.2 inch heat sink from heatsink usa but shipping was ridiculous! I'm going to try to find a local computer store to get one. Otherwise I'll get some aluminum and attach fans to it.



I'm going off this post
http://www.plantedtank.net/forums/li...ml#post1281039
as far as par goes. He got about 110ish PAR at the substrate from his fixture with 48 LEDs, so I'm hoping with less LEDs I can get to my goal of about 75 umols

I realize this will still put me at pretty high light, but I will lift the fixture and hopefully this will 1. reduce the PAR, and 2. help the light spread out better.

Our local club has a PAR meter that I can use so I'll provide solid numbers once I finish.

Here is the proposed wire up. It's not to scale or anything, but it gives you a general idea. 2 "arrays" on the side, and a big "array" in the middle.



Any help and what not would be great!

[Hoppy]

Those look like great LEDs for an aquarium, but I notice they are for a maximum of 700 mAmps, and the Meanwell driver you are getting will drive them at 1050 mAmps, maximum. You will need to use an ammeter to adjust the driver down to 700 mAmps before using it.

Judging by my LED light, using 130 lumen LEDs vs your 220 lumen LEDs, you might get about 80 micromols of PAR at 18 inches. I think I would try to evenly space the LEDs, about 3-3.5 inches apart, leaving the middle of the fixture blank because of the cross brace on the tank. And, I think I would use all 30 LEDs, in two 15 LED strings. Meanwell drivers have an adjustment screw for the output voltage, so you should be able to raise the voltage enough to accommodate 15 LEDs. You could then use 3 rows of LEDs, 10 in each row, spaced 3.25 inches apart, with about a 6 inch gap in the middle. This would be close to my setup, except with about twice the PAR.

I don't think you need a finned heat exchanger for this. Look at getting aluminum channels, 1/8" thick aluminum, one channel per row of LEDs. In fact, this would be a good time to do a lot of thinking about how you will house the heatsink, or whether you want the heatsink itself to be the housing, and how to hang it. Ebay has some stores that sell aluminum channels - Online Metal Supply is one.

[IWANNAGOFAST]

My tank is a rimless 48 gal mr. aqua tank so no brace.

How would I lower the mAmps using an ammeter?
I have one of these
http://www.sourcingmap.com/digital-l...aign=usfroogle

I was reading your thread hoppy and the closer the LEDs are the higher the par right?

[Hoppy]

Originally Posted by IWANNAGOFAST

My tank is a rimless 48 gal mr. aqua tank so no brace.

How would I lower the mAmps using an ammeter?
I have one of these
http://www.sourcingmap.com/digital-l...aign=usfroogle

I was reading your thread hoppy and the closer the LEDs are the higher the par right?

Those LEDs produce a 90 degree cone of light, so the light from many LEDs hits every spot on the substrate if they are close enough, and the closer together they are the more LEDs contribute light to every spot. Mine are about 3.25 inches apart.

Originally Posted by IWANNAGOFAST

Ok, I just called in to change my order to 3 of the 700 mAmp drivers, and added 6 more LEDS to bring the total to 36.

I guess I'll just do 3 rows of 12 evenly spaced instead of clumps of LEDs.

Good idea Hoppy. I'm tapping into SFBAAPS to see if anyone knows of a local source for heatsinks or aluminum channels . I'd rather not get it shipped since shipping would probably be pretty high.

The 700 mAmp drivers will work easier, because they limit the current to 700 mAmp, and, I just noticed that that model driver is not adjustable. It produces 700 mAmps and only 700 mAmps. It self adjusts the DC voltage as needed to power the LEDs. My driver has a removable cover that gives access to a couple of adjustment screws for current and voltage.

Your tank is about 3 inches more front to back than mine, so you might want to make the 3 rows a bit further apart, perhaps 4 inches. That will reduce the PAR, but probably still give you close to the amount you want. Since you don't need the ends of the tank quite as bright as the middle, you could space the 12 in a row at 2.75 inches apart, so they stop about 3 inches from the ends of the tank. That raises the PAR, bringing you back to about the amount you want.

If you don't mind a trip to Sacramento, you can find lots of aluminum extruded shapes, including about 5 sizes of channels at: http://www.bluecollar-supply.com/ And, several years ago there was a similar store in Oakland, but it may not still be there.

[IWANNAGOFAST]

Ok, I just called in to change my order to 3 of the 700 mAmp drivers, and added 6 more LEDS to bring the total to 36.

I guess I'll just do 3 rows of 12 evenly spaced instead of clumps of LEDs.

Good idea Hoppy. I'm tapping into SFBAAPS to see if anyone knows of a local source for heatsinks or aluminum channels . I'd rather not get it shipped since shipping would probably be pretty high.

[DiscusLoverJeff]

Iwannagofast,

When you all done with this great project, can you possibly post a total cost? I am looking to build 3 fixtures, 1 for my 36" reef and 2 for my 48" plant tanks.

Good Luck!

[IWANNAGOFAST]

will do Jeff.

[IWANNAGOFAST]

Thanks Hoppy, I'll look around for aluminum channels and if I can't find any I'll make my way to sacramento.

Tom mentioned that I may have way too much light, so I'm going to wire up 2 rows of 12 10 inches apart, then add a middle row as necessary to increase par.

Very good discussions, very good at keeping me from doing my work... haha

[Hoppy]

Since each row will have its own driver, you could easily add an on-off switch to each driver's AC power side, then you could run any combination of 1,2 or 3 rows that works best. For the slight added expense and trouble, you avoid having to take it apart and add a 3rd row if needed. I would definitelly do it that way.

[IWANNAGOFAST]

Originally Posted by Hoppy

Since each row will have its own driver, you could easily add an on-off switch to each driver's AC power side, then you could run any combination of 1,2 or 3 rows that works best. For the slight added expense and trouble, you avoid having to take it apart and add a 3rd row if needed. I would definitelly do it that way.

I didn't think about including the on off switches, I never use the ones on my current fixture since they're on timers.

I was hoping, if I end up having enough light with just the two rows, I'd be able to use the leftover LEDs for a small fixture on another tank. So I don't want to install all 3 rows in and end up only needing two. Plus I'm not drilling my heatsink, I'm going to be using the thermal adhesive to mount the LEDs.

[jcardona1]

Nice to see you start off! I'll be following this thread to see how it goes. Once I get my stand built and the tank plumbed, my next focus will be the lighting

[IWANNAGOFAST]

Ok, ordered some more stuff today, didn't want to waste time searching for heatsinks in dinky warehouses so... this is what I got. This is starting to get expensive haha

3x Flat aluminum bars (1 inch wide, 1/8inch thick and 36 inch long) 34.90 after shipping
added 6 more LEDs for 12.23
Added a fan kit from rapidled.com plus a 3rd power cord - 31.79 shipped

Just need now : Fans, I think I still have my old computer case which I can salvage the fans from... I hope...

Total spent: 260.20

lol... this is not cheaper than replacing the bulbs...

[Wicket_lfe]

man just like you, i need to poop or get off the pot.

goodluck with this project, ill be keeping an eye on it.

I just did my pricing and will be spending about the same on CREE LEDs, i think? LOL

[IWANNAGOFAST]

haha, Cree's aren't cheap but I guess they're the best out there right now.

I'm hoping that 2 rows of 12 LEDs each will be perfect, and I can use the leftover driver and LEDs to build something for another tank.

Now I just need another tank lol.

[Hoppy]

Based on this, http://www.plantedtank.net/forums/di...d-fixture.html you should have a very well lighted tank.