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My Hydro Habanero's: DWC with DIY LED's

Hey everyone! I am glad to have found a pepper specific forum where lots of other people understand the urge to create artifical environments and control them :)

Not sure why, but I have recently become addicted to eating fresh habaneros! There is this complex aroma and taste that you get before the hotness kicks in that I haven't tasted in other peppers. So even though I can barely tolerate the heat and it takes me a while to eat one, I can't seem to stop craving them. I cooked some with meat and cheese then was sad to have run out.... so decided why not grow some! But oh nos it's winter soon... better grow them indoors :)

I've also been itching to try my hand at hydroponics, so it was a perfect match. I am a big DIY LED nut for SW aquariums so I had all kinds of extra LED's from past projects. I ended up making a 100w fixture using mostly Cree LEDs. This made the project "cheap" for me as I had sunk costs already.

LEDs:
7x Cree XPG R2 bin, Cool White
8x Cree XR-E Q5 bin, Cool White
4x Cree XR-E Royal Blue
6x Cree XM-L Warm White
2x Cree XP-E Red
2x Luxeon Rebel Far Red
2x Luxeon Rebel Amber

leds.jpg


Drivers:
The XP-G's are on a non dimmable, 24w Xitanium supply.
The White and Blue XR-E's are on a dimmable Meanwell 60-48D power supply.
The Warm XM-Ls and Red LEDs are on a separate Meanwell 60-48D

You can see the potentiometers on the right-front of the black box. Also got some pulleys to give the lights about a foot of adjustment range.
pulley.jpg


All of the LED's use Total Internal Reflections optics by Carclo. I first tried a mix of medium and some narrow lenses, but there was too much spotlighting unless you get a few feet away. Ended up using all Wide lenses.

Hydroponics:
Deep Water Culture, 2 plants in a 4g reservoir, water level a few inches below net pots.
GeneralHydro nutrients, only Bloom and Micro. This is known as the Lucas formula.

The correct thing to do would have been to use seeds and start from there, but I was impatient. I ordered some plants off amazon. Thought they would be young by the description (2"pot), but they arrived with a date, showing age 95 days. You can bet they were very rootbound and hard to transplant, but they made it! They even came with a few immature peppers already, but all the flowers fell off in the box in shipping.

Sadly I didn't take pictures until they were transplanted into my DWC system for about 10 days, but the leaves were all really curly like kale on arrival. They also had a slug, a few aphids and whiteflies. I have learned my lesson, pests in this hobby are just as pervasive as in the coral trade it would seem.

The first few days of hydro, the plants both turned pale yellow and dropped bottom leaves. I think I had the waterlevel too high (1" below netpots) so have since increased the airgap to 2.5" and it really helped. Dropping stopped, and gradually things started looking up.

The plants after 10 days. The pepper on the right had grown and turned red already. The redness happened literally inside 12 hours. I think stress may have accelerated it. The leaves look messed up. They are more yellow than when they arrived, but less kale-like.

peppers_01.jpg


The plants were pretty sparse with almost no small leaves and only 1 flower, and three peppers.

peppers_02.jpg


Here are the roots after the same 10 days. The darker yellow ones came from original soil, but the white shoots were all new and reaching into the solution.

roots.jpg
 
Now get ready for this. These are the same roots only 6 days after the last photo!!

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Reaching into the solution nicely as well:

04.jpg


Seeing at least a dozen small bud sites and new growth everywhere. Today photo:

03.jpg


These next two are from yesterday but do a better job of showing the plants than the ones I took tonight:

update_03.jpg


update_02.jpg


And this is a photo from tonight. Gives you an idea of how the space is set up.

01.jpg


The 2 peppers on the left plant were very tiny a week ago, but now they are 3/4 the size of the one that turned red already (btw the last one was yummy but not the best one I've had).

Will post more details on parameters and lighting soon.
 
Going to discuss the lighting a bit then nutrients and others.

I have measured output of the fixture under various configurations using an Apogee PAR meter. When I had the medium optics, the fixture was capable of acheiving 2000 par at about 2' away from the fixture, and even higher closer. The problem was that I didn't evenly distribute the different colors well enough for the medium optics to prevent color spotting. And also when I carefully took small measurements, there were some gaps and hotspots which is not desirable since you could burn some leaves.

If you have alot of space, using medium or even tight optics (6' space from plant to light minimum IMO for the tight optics!) can be a great way to optimize the lighting, but it's too narrow for close range lighting in most cases. So I switched to wide on all of em. Gave me alot more even coloration with my particular blend of LEDs, and more even readings.

Going wide did reduce the 'throw' of the fixture a tad. Now you have to put the sensor around 12" or closer to get the 2000 readings, but that's not so bad. However right now the LEDs are at their lowest possible height, and it's about 18" to the plant tops. The max brightness I can give the plants at this distance is about 1500 PAR, but they are only currently getting 1000 PAR. I have slowly been increasing from a starting point of 400.
 
As previously mentioned, I am using the Lucas formula, which involves only the Bloom and Micro parts of the normally 3-part GH hydro.

I have been using carbon filtered tap water with an EC of 0.25, and mixing the nutes to about 1.7 EC.

A few days ago the EC was trending upwards, so I'd top off with fresh water. But as of the last 2-3 days, EC is now trending downwards. It is now at 1.6. I guess this means the plants can handle the current nutrient amounts safely?


I swear some of the leaves and new growth have that 'pinched' edge on some of the younger leaves that I have associated with nute burn. But other parts look like there are deficiencies. Am I reading too much into the details of the leaves for a plant that's still basically recovering??


To help the transition from soil to hydro, I have been adding a bit of "EWC/Myco" tea that was brewed with molasses and some air stones. Supposed to outcompete the bad fungii and bacteria and also colonize the roots with helpful good guys. Not sure to what extent the tea has helped, but I am pretty happy with the results so far on the rootzone.
 
wow great looking setup, i love that you are using those led optics. i used to fool around with led flashlights, and i had a bunch of optics from cutter.

had you ever considered the mce leds or are they too expensive?
 
Thanks. Yea the optics are pretty fun. I've been meaning to throw together a little DIY led flashlight out of some 1/2" pvc one of these days :)

I have actually used the MC-E leds for my saltwater application. They had particular importance there, because I was supplementing T5 lighting. I wanted the "shimmer" effect from having point lighting (typically halides), which looks like lighting underwater in the ocean (caustics). So by having a single brighter light, you get a more pronounced shimmer than the same light distributed over 4 equal points.

The MC-E is basically 4 xres crammed into a small space. If you really want to use less LEDs, or need the point source factor (like for a flashlight), then great. But there's a decent loss of efficiency because they are putting that much more heat into one little area. There is also the fact that they run around 13v which makes them impractical to drive with most commonly available drivers. You end up with alot of wasted potential, and need more drivers as a result. Unless of course you are just using a DC power supply and not using drivers (doing all the driving manually, putting in resistors, adding fuses, making sure you account for overdrive current if one fails bla bla bla, not recommended unless you're an expert). There are some meanwell 200+ watt drivers you would need to run multiple MC-Es.

So it's doable but for hydro IMO it's better to get slightly cheaper LEDs and take advantage of more even spread. XP-G R5 can be bought for 5 bucks on dealextreme!!! I'd rather take advantage of having more small evenly spread emitting points, because that setup is more likely to deliver light to inner/shaded parts of bushy plants. Of course if you have light movers, it can mitigate some of these factors. Remember the sun is over 2000 PAR but each part of a plant only recieves that intensity for a few hours for most locations, the rest is partial shade which can be much less. But since the sun moves, even the inner leaves that are totally blocked from above will get some sunlight at some point.

It's definitely doable. If you found a really good deal on them I'd say why not. But make sure to get series, not parallel wired version..I made that mistake once :D
 
i see what you mean, i hadent thought of that honestly.
what do you think of the led fixtures out on the market currently that only use red and blue tints? i had always wondered why they did not use any white at all
 
I don't have alot of experience with those types of fixtures, but I have seen some like the UFOs. The problem isn't the light spectrum, it's the fact they are using 5mm leds without optics. The light doesn't cast very far as ALL and you don't really get sun-brightness PAR values, not even close. I kinda want to bring my PAR meter to a local hydroshop and test it out since they have these lights. Both red and blue light are within the Photosynthetic range. But it's also better to have a nice smooth output over the full range than concentrating all the output on a specific band, since different frequencies have different effects on the plant, but I'm not really an expert there.

Because of this, LEDs are inherently more narrow banded than MetalHalide or HPS. All white LEDs are actually Blue LEDs (LEDs can physically only 'emit' one color), and the outside is coated in a phorphor material that is able to step down the higher electron charges, bringing down the color temp. So phosphors can only make light WARMER, so you can't turn a red light into a white light, only the other way around. So no matter how good the phosphors (and it does matter), you still get a HUGE spike in the blue range, and then a nice calm hill covering the rest up to red.

As far as LED fixtures go I would personally run the other way from any fixture that didn't have individual optics for each LED, and ESPECIALLY if they don't specify exactly what model of LED. The range of efficiency is massive. Cree's are almost twice as efficient as Luxeon's (except the rebels), yet sometimes people will spend thousands of dollars on luxeons because they didn't research carefully. Those might be fine for decorating your house, but you are throwing money away if you want to grow with them.

Luxeon does have a Tri-Rebel that is pretty similar to the MC-E but actually slightly better IIRC since it doesn't have as bad of a heat-packing issue.
 
FYI, these type of fixtures are basically the same thing I made, but look way nicer, and cost 5x as much :)

AquaIllumination, 24 cree LEDs, but costs 1200 bucks!!!!

Not sure who makes this, but its got 20 LEDs, for $500. Much better deal but still twice what it would cost manually.


Also keep in mind that the above fixtures are for Corals, so are focused on cool-white and royal blue LEDs. It will probably work just fine, but won't have much red light. I honestly am not sure how important that is. Some people claim it encourages flowering to have sufficient red light. I'm sure some retailer will have options since some reef people prefer warmer colors. I could probably make another copy of my fixture for 250-300 bucks, and it has more wattage than both of the above fixtures, though only 20% more than the first fixture.

Of course you will most likely be getting more average binned LEDs with those preassembled fixtures. If you shop for bins and get higher numbers (Q5, even better is R2+), you will see higher efficiency.


To answer your question about why red/blue LEDs are common... this is just my guess but I would say it's because 5mm LEDs in a single spectrum are cheap, both colors are within PAR range, and there is actually an effiency loss involved with phorphors. And those fixtures output so little light maybe they can't afford the loss??? White LEDs with phosphors can be more expensive... just a guess. Another possible reason is plants don't need much green light, and white LEDs do waste some in that range.

With optics and high quality LEDs you get so much light that the phorphor loss becomes pretty meaningless.
Also I don't mind a tiny bit of "wasted" green light, it makes the plants appear more natural and easy to look at!
 
The last 5 days have been pretty good to say the least.

01.jpg


Upon first glance it *appears* some leaves are drooping, but upon closer inspection, you can see they aren't drooping, they are actually growing sideways to capture the bounced light from the white walls and door. I have measured that the sideways leaves get a PAR increase of 50-100 PAR when closing the closet door (but then I cannot take a photo!)

In this photo, the growth is almost like the what you typically see in vertical grows - sideways tops:

02.jpg


some upside down new growth:

03.jpg


In this photo, you can clearly make out the original leaves by their ugly grey appearance and thin yellow edge. They recovered to ~75% and then just stopped, and the plants focused all growth elsewhere. They are also the leaves with holes in them :)

04.jpg



Circled in red is an example of a leaf that had obvious signs of nutrient burn last week when I was using ~2.2 EC. As you can see, the leaf has grown tremendous in size, but still bears the scar of previous growth pinching.


Most of the new buds lookin nice:

05.jpg


On the right plant, in several of the top areas, all of the new growth is dying back after growing to ~1/4" or less. It seems a darker color from the onset. Here's a great shot of it:

06.jpg


Could that be a sign of light burn?? Or maybe some localized bacterial/fungal issue? That spot gets around ~1100 PAR right now, and it seems some of the new growth is getting on just fine. Maybe just some sort of automatic pruning based on conditions going on here?

As shown above, most of the buds look nice and have a green stems, but the topmost ones have slightly darker stems, almost like very fine black lines running down the stem. Is that some sort of end rot???



Overall I am very happy with the performance of the setup so far. It is very interesting to see how the same plant has developed such small thick leaves up top, and broad thin leaves below that orient to the walls (or aluminum foil on the lid) in order to absorb as much light as possible.

There has been very little vertical stretching of the plants so far. I am wondering if I should prune off the old ugly leave to free up some room. I think the extra density comes from transplant shock plus intense lighting from above, and moderate lighting from all sides.

Right now I'm at an EC around 1.5 and ph of 6.
 
what are you using to measure par and where can i u buy one.

also id guess the issue with the tips is nutrient related, whats the breakdown of the lucas forumla? mg/l wise anyway

ive used the howard resh nutrient profile for peppers with great sucess, you might want to compare the two.

http://www.howardresh.com/hydroponic-culture-peppers2.html
 
Hi,

I am using the Apogee Quantum Light Meter. However I learned *after* I bought the expensive instrument that you do NOT have to buy the complete meter and sensor. If you have a multimeter with a detachable probe... you can actually buy just the PAR sensor from Apogee (licor is another good brand), hook it up to the multimeter, and you multiply the mv reading by 5 to get PAR. So you can have a PAR meter for like under 100 bucks ;) If only I knew that before hehehe.

The labels for GH nutes are
Micro:
N: 5%
P: 0%
K: 1%

Bloom:
N: 0%
P: 5%
K: 4%
Mg: 1.5%

CalMag (since I use a small bit still)

N: 2%
P: 0
K: 0
Ca: 5%
Mg: 1.5%


I'm using about half the recommended dose of The Lucas (Bloom+Micro), which makes an EC around 1.2-1.25. My tap water has an EC of 0.25.

I then add about 1/2 dose of Calmag, which brings the EC up to ~1.55.

Is that enough info, or were you also wondering about the micro elements like iron, mn, mg, bo etc.


After typing all that out.. maybe I'm giving the plants too much Nitrogen (from the Calmag) and not enough P or K?

I only started adding Calmag since I thought I had Mg deficiency (prolly was just stress), but now I realize that Bloom and Calmag have the exact same Mg content :) so I might as well just use more of the Bloom, right?

Since I am using tapwater it's doubtful I need the 5% CA in calmag. What do you think?
 
*edit*

I am dumb, the sensors are for sale right on Apogee's main website.. you just have to expand the little "Order Sensors" menu on the left. $139 for just the sensor is a pretty good deal. All you need is a multimeter, plug it in, read in mv, multiply by 5, and you got a PAR meter :)

you only need the cheap one. the more expensive ones just add gain, so wouldnt need to multiply by 5.
 
Those HowardResh nute profiles are very interesting!

Twice as much K as N recommended, and very little P.

With Lucas, it's not possible to get those levels since the Bloom aleady has more P then K, and Micro has almost all N, very little K.

Wonder if that could be my problem?? What nutes do you recommend to get those levels?
 
i make my own fertilizer from the usual salts, but do you have all three gh bottles? i came up with a profile way back that came pretty close to the resh numbers using just the three bottles + epsom salt. when i get home i can look up what i used.
 
Nope, I thought I could save money by skipping the Grow. But now I will definitely check it out.

Looks like Gro is 2-1-6, so I would be able to up the K fairly easily. But I think it's odd if I'd be the only person to have an issue with the Lucas formula. After all, Lucas himself has shown plenty of healthy plants using it. But maybe since my peppers were grown in soil and transplanted they have different requirements?


I also have some Potassium Chloride that was made for aquarium use... but I wonder if I could also just use some of that?

Thanks for the help.
 
I came across it on the garden web forums where lots of people use it for everything. Lucas himself posted a lot there last year and included lots of pics of pepper plants. Not sure if Lucas is from cannabis or normal gardening originally though. He doesn't seem to be active currently. I'm not getting much response there at the garden web forums about it.
 
You do remind me that it's almost impossible to research nutes/hydro/aero without reading a lot about cannabis. Sometimes the only equipment discussions for things like nozzles etc are in cannabis forums. Pretty funny.
 
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