High-Power LED Fixture for a Planted Tank

[BigJim]

It's really more of a design and proof of concept rather than a build thread. Here's my fixture. Here's what it can do.

I suppose it is a bit hypocritical that I don't have a background. In my defense this wasn't supposed to be the tank I did the LED build on. I was going to do it on my 40B, but I chickened out because I had zero faith in my electrical skills and I wanted to minimize the financial hit when all the magic smoke escaped from the circuit. I've been debating whether I should try a black laminate background, try to figure out how to paint the back of the tank with it set up, or just leave it and grow the plants thick enough to block out the back glass.

Thanks. The scape is a work in progress. I actually just pulled out the wad of guppy grass because it was annoying me and I spread out the telanthera a bit. The little cave/castle is actually my wife's. She likes it in the tank, so I leave it there. She actually wants to put a bigger, very similar castle in the tank. I feel like the tank needs some kind of hardscape, so we'll see.

I'm pretty excited about the glosso at the moment. All the new growth is practically flat on the floor of the tank. It's going to look like the tank is tiled with little green leaves at this rate.

The light green plant in the back left corner is asian ambulia. I didn't realize it was so demanding of light when I traded for it, so it died back to just a few sprigs. It's coming back nicely now and I'm hoping it'll get back to the thick bushiness it was when I got it. I can actually see how much it grew today alone.

 

[Hatty]

I don't have a background on my 30 gallon tank. I was planning on putting a black piece of plastic behing the tank like I did on my old 10 gallon, but I decided against it. I, working towards grossing a wall of anacharis in the back but not to the point where it completely blocks out the back wall. I like being able to see light behind the plants. It makes the aquarium seem bigger and not so cramped.

 

[mfdrookie516]

Jim, I call dibs on the first trimming of the ambulia (maybe we can trade some plants at that point?)... I'm searching hard for it... since some is illegal, nobody seems to carry any. I got some from KaiofCanada a while back, the only legal kind I know of, and it all died from my noobism to plants. I thought thats what it was, but wasn't sure.

 

[BigJim]

I would actually disagree with that. I think a dark background really gives the tank a sense of horizontal depth. I like it so much on my 40B that I wish all my tanks had painted backgrounds.

 

[BigJim]

mfd, I think I actually got the ambulia from FishEggs here on AA. You could try PMing him. Otherwise, you've got dibs on the first trimming. I haven't found anything saying asian ambulia is banned in Illinois, just that it's an invasive species and you're encouraged not to propagate it. All that means is I have to be responsible with any trimmings I have.

 

[BigJim]

I got my phosphate, nitrate, and hardness kits today. Here are the readings I got:
NO3 <5ppm
PO4 1.0-2.0ppm
GH < 17.9ppm (solution turned to final color with one drop)
KH 6dKH

Looks like I need to add some nitrate and reduce the phosphates in my fert mixture. I also need to do something about the GH. I'll have to do some research.

Full tank shot

The telanthera is looking awesome. The top half of the stems are almost blood red.

The nesaea is doing ok. I was losing some of the lower leaves so I spread out the stems.

The rotala is finally starting to grow noticeably. The moneywort is also growing nicely. I can't believe how bushy it's becoming.

The asian ambulia is growing quickly. The light green parts of the plants are new growth from the last week or so.

The glosso is starting to fill in. Keeping some of the small pieces planted has been a real challenge.

 

[Hatty]

I'm loving how everything is looking. I'm excited to see how the glosso turns out. I was thinking about going that route for ground cover, but decided on dwarf hairgrass instead.

My GH (=170ppm) and KH (=20ppm) are polar opposites of yours. I've been working to get them lower but the won't budge. Now, it could be the test kit I have. I use the strips that test a lot of things at once, but I've heard they aren't very accurate.

So, I've finally finished my LED system. I have two parallel strings of 6 lights in series (12 total LEDs). The LEDs are XR-E R2WC which put out 118 lumens nominal. I glued them to two pieces of aluminum L-rail which I then bolt to my aquarium hood. They are driven by a 1A Buckpuck (as I mentioned before) which uses about 22 watts of power and produce a total of ~1,850 lumens. The rails are fairly effective at dissipating heat. With all the LEDs, driver, and power supply tucked inside the hood, the temperature of the L-rail behind the LEDs gets up to 110 degrees F. With a fan installed, the temperature is 80-90 degrees depending on the fan speed.

The only problem I have with the system is the excessive amount of light flickering because of the rough water the filter outputs. It kind of gives the tank a strobelight effect. Have you experienced similar things with yours?

I'd like to thank you, though, on motivating me to get my lighting system done. I've been dreaming about this for a while and your success pushed me. I included a picture of my tank below along with the plants and inhabitants:

Dwarf Hairgrass - front right
Anacharis - Back right
Variegated Baby Tears - top left
Java Fern - back left
Java Moss - front middle

1 Chinese Algae Eater
1 Apple Snail
2 Ghost Shrimp
2 X-Ray Tetras
3 Glowlight Tetras
3 Zebra Danios
3 Dwarf Sunset Gouramis

I have DIY CO2 and have recently begun adding Flourish. I'm trying to do more research on ferts, so hopefully I'll be able to begin adding those soon.

 

[BigJim]

Glad to hear your LEDs are up and running. I looked at the XR-E R2s, but they were more expensive and harder to find any information for than the Q5s I used. I don't think Cree even had them listed on their page.

I get the strobing effect. The best way I've found to combat it is to fill the tank up so the water is touching the glass canopy. This stops the surface agitation, limiting the strobing effect. It has the side benefit of trapping the CO2 more effectively also. My 20H isn't sitting perfectly level, so I generally fill the tank so the water is touching half to three-quarters of the canopy. It's a nice compromise where I still get some shimmer effect, but it's not obnoxious.

You're off to a good start with your tank. It needs more plants! I've had a lot of trouble with anacharis and hair algae. I have a hunch that anacharis sucks down the nitrates without using much phosphate. I've also noticed that java fern grows better under lower light. As an experiment, I threw a couple baby ferns in my 20H with the ferts and the high light and they didn't grow as well as the ferns in my low-light 29g.

I think you might have some trouble with your fish list. CAEs get big and aggressive and gouramis usually don't like to get along. Just a couple issues to watch out for.

Look into the PPS Pro regimen. It's cheaper than the EI dosing and requires minimal testing once you get your ferts balanced.

 

[Floyd R Turbo]

Sweet build! I've been reading up quite a bit on LEDs recently for SW applications. I haven't seen many FW builds, and planted even less.

I just breezed through this thread so forgive me if I repeat something...but here's my 2 cents...

w/r to comments about cooling, the heat dissipation properties of U-channel is plenty if the fixture is in open air and the LEDs are more than a few inches apart. If you want a longer explanation, I can go into the maximum operating junction temps and why they are never reached in open-air fixtures, and why it really doesn't mean much even if they are because by the time your driver burns out (which will likely happen first) you'll upgrade your LEDs because it will be cheaper to do that....but I digress!!

As far as the square channel, check out Home Page there is a blower fan that fits into the end of the tube and blows through it. Perfect for square channel.

Pressurizing Cooling Fan

Actually originally designed for a TV that isn't in production anymore, so it's like $16. But you still really don't need it if you go with U-channel. Square channel, maybe.

As for water cooling - overkill. Just like those huge finned heatsinks. Not necessary, unless you want the warm fuzzy. You can even make fixtures with the LEDs mounted to a sheet of aluminum and put little CPU heat sinks (less than $1 each) on the back and that works too, no active cooling.

Just curious if you are concerned about the location of your power supply?! Putting it on top of the tank like that seems like you are asking for an accident, and it would decrease the lifetime of the unit because of corrosion. Why not just set it off to the side of the tank or in the stand?

 

[BigJim]

I decided to keep this a minor engineering project by foregoing most of the heat transfer calculation. The square channel has worked for me so far. It's warm to the touch, but not outrageous. I may have to add a fan in August when it's hot, but I'd like to avoid adding any more circuits to this fixture if I can.

I'm not really worried about the power supply location. The fixture all but clamps onto the tank and I've got a glass canopy between the fixture and the water. No salt creep to worry about either. I like the power supply where it's at because the metal box and frame help dissipate the heat from the supply.

If you saw the mess I can make doing PWCs and trimming, you'd understand that everything electrical is safer above the water line.

 

[Floyd R Turbo]

Yeah, that's true!!! I would say you're fine for cooling, if it's cool to the touch you have nothing to worry about. The human pain threshold is something like 148F and the maximum operating junction temp of most LEDs is 150 Celsius, which is what the useful life (L70) is based on. Your build is a perfect example of why you don't need mega heat sinks and tons of fans.

I just posted that for anyone interested...

 

[Hatty]

Ill have to try pps pro. It looks complicated but I guess I just need to bite the bullet.

Filling my tank to the brim might not work well since I have a marineland biowheel and they can get loud if the water level is too low or high. But ill experiment.

I actually got the r2 for the same price at q5 so it wasn't that bad. But if that wasn't the case then I wouldn't have bought them. They are much more expensive with just a little gain.

I haven't gotten any hair algae on my anacharis yet but ill keep an eye on it. I knew the java fern was going to die with the high light but I thought id try sticking it in a shaded part of the aquarium to see how it does. You have any ideas on what other plants I can add? The baby tears will eventually cover thetop of the wood but its taking its time.

The gouramis I have are quite peaceful or so I've read. They get along very well so far bit as they get older that might change. The cae was a mistake but im fond of him so im not getting rid of him. But he isn't very mean to the others. That's because I hit him with "the white stick of death." So, every time I see him being mean to the others I will chase him with the stick. He bas gotten to the point that when he does someting bad and he sees me approach the tank he will dart behind something and hide. He is quite smart. And the size thing doesn't bother me too much. He is about 4 years old and has only got to 2.5 inches. Its looking like he will stay a runt for the rest of his life.

 

[BigJim]

Sorry for the long absence. Life's been keeping me busy.

I've got pictures, but the computer with the SD card slot is down for a few days while I replace the screen, so you'll have to settle for a written update.

I actually had to trim the glosso to keep it in check. It's running rampant and spreading to the back of the tank where I don't want it. It actually burrowed under the castle and started growing inside. I used the trimmings to fill in a few holes in the carpet. Give it another month and I don't think I'll be able to see sand.

I can see why ambulia is considered a noxious weed in some places. It's been growing at a rate of 1/2"-3/4" a day. I'll see a little silver frond when I leave for work in the morning and come home to a fully open leaf with another starting above it.

The nesaea has been losing it's terrestrial leaves like crazy, but it's also been growing new aquatic leaves. The aquatic leaves are longer and more slender. I think I like them better. I'm just getting tired of having to skim nesaea leaves of the top of the water.

The rotala and the moneywort don't seem to want to grow much. I'm wondering if they're getting beaten out for nutrients by the faster growing plants.

I've had one setback since I last posted. I've had an outbreak of hair algae on the upper leaves of the telanthera. I've got a few possible reasons:

1. The CO2 line may have pulled out of the powerhead, limiting the distribution for a few days.
2. The cylinder is getting empty, so I'm questioning the quality of the gas.
3. I wasn't adding enough CO2.
4. I haven't tuned my ferts well enough yet and I've got excess phosphate.
5. My little HOB filter is off-gassing too much CO2.

I haven't built a drop checker yet, but the fish aren't gasping at the top yet, so I upped the CO2 rate to 2-3 BPS and made sure the CO2 is getting into the powerhead stream. My tank has been consistent at 5ppm nitrate and 2ppm phosphate, even with a heavy fish load. I've been working on a fert calculator, but I still need to add a little bit to the file before it's finished. In the meantime, I've got some phosphate remover that I might try.

 

[meegosh]

Do you have a kh and ph test kit? You could get a rough idea of how much CO2 you have by measuring those two. IME, I've found hair algae creeps up when your micros are in excess. I think that was the case for rookie too. It could be caused by other things but it seems excess micros is always the culprit in high tech tanks.

I've modified my AC50 slightly by using silicone to attach a piece of plastic under the outflow. This allows that water to flow down into the tank, creating far less surface agitation/off gassing.

 

[mfdrookie516]

Yeah, Steve, once I got my PPS Pro autodosers set up, the hair algae has slowly started to retreat. It was definitely too much of something I was dosing.

Jim, FWIW, my co2 was empty Sunday morning. I had to get it refilled yesterday. Not sure if I had a leak or if it was just from running 2 tanks. I leak tested it yesterday and found nothing though.

 

[BigJim]

Good to know guys. I'll try cutting back on the micros a smidge and see what happens. My goal this week is to build a drop checker to eliminate the guesswork with the CO2.

 

[mfdrookie516]

A very good idea! I wouldn't have the patience to test all the time.. its so easy just looking at the drop checker.

On a side note... I know this isn't a classifieds ad... but if you ever need to offload some ambulia, hit me up. I've looked everywhere for some.

 

[giggalz]

wow from the picture of the tank with the guppies is gorgeous..they are pretty even from that far away ...

 

[BigJim]

Thank you giggalz. My wife decided she wanted blue guppies about a year and a half ago. We started with four and I have to unload some on Craigslist every month or so to keep the tanks liveable. These are just the extras from my 20L.

Tank update: The plants seem to be enjoying more CO2. The ambulia is growing even faster and I saw some pea-sized oxygen bubbles roll off the leaves of the glosso. I cut my micro fert dose from 2mL to 1.5mL today. I'll try it for a week or so and see if the hair algae recedes.

 

[BigJim]

I've been cutting back on the micro fert dosing and I think the hair algae is getting worse. I'm going to try it for a few more days and see what happens.

Water parameters:
pH: 6.8
PO4: 2-2.5ppm
NO3: 5ppm
KH: 6dKH
GH: 10dKH

According to a pH-KH table, I'm running about 28ppm CO2, so I'm at the high end of the good range.

I finally got around to fixing the computer and taking some new pictures.

The tank is getting pretty bushy.

The ambulia has reached the top of the tank. I'll probably cut it and plant the tops at next PWC.

I keep pulling the algae covered leaves off the telanthera, but it's still pretty thick.

The new aquatic leaves on the nesaea are growing densely.

The glosso is growing like a weed.

Here's an interesting shot. The glosso is growing right up against the glass and you can see the roots. The sand is about 1.5" deep from the surface to the tank frame and the roots go all the way down and keep going.

And lastly, a shot of the dastardly hair algae.