The LED hack shack and other tall tales

Hello there fellow growers!

Been away from growing for a long time, but found my way back and have started to grow again.
Started out at the drawing board, planing everything out and going over old equipment.

First part of the build was a 2x 600W HPS flower room, with a simple flowtable setup and a 66 Gal res.

Next I would need a place for mom’s n clones, and space wise a good closet would meet all the needs.
Only problem it’s a pain to cool a HID light in that small space, so LED came to mind and I had a little laugh to myself.
Not trying to piss anyone off, but I had the images of LED grow’s 10+ years ago.
Started reading and I found a bunch of nice looking results, it was very clear the LED lights had improved ALOT in the past decade.

To the drawing board once more, planing drawing and calculating prizes.
Went over a bunch of different layouts, untill I ended up with this plan.

Now I just needed a little plywood, paint and a few other essentials. Like LED’s

Let’s see LED’s - we’ll just google that and buy some good once…
Okay, so we got LED chips, Cob’s, passive and active cooled, white and burple spectrum.
WTF … there got to be someone who have tested this things, I just need to read a little more and I’ll find my answer.

I found like always, people are people and everyone wanna impress others. Everyone was super happy with the lights they build, even tho there where massive difference in the results people got.

Eventually figures out LED chips where the way for me, as I was aiming for low heat and not most Par light per watt.
Now I started talking with people growing under LED strips, everyone seemd to be talking about one specific Samsung chip. The Samsung lm561c from 2015.

Ohh look and behold, the mighty and glorius price id have to pay for these lights.
No local option to buy, shipping + import tax + handling fees, simply made it too expencive!

But hmmm 2015, 16, 17, 18 … I wonder how far China is with copying that…

Can I build an effective growlight, from cheap stuff I can order on ebay?
I can import as much I want from china, as long the shipment is under 14$

A lot of orders later! (I am still waiting on parts)

Starting the build:
Step 1 Find a clear spot, where you can feel your zen!

Step 2 Sit down and meditate, imagin your build and how the end result should look.

Step 3 Your done!

That was pretty easy, let’s hope the DIY LED stuff I know very little about is just as easy.
It’s electronics how hard can it really be?

I have basic understanding about a lot of things, Low volt DC and electronics is not my strong point.
But it’s DC 12 - 24 volt, it can’t really kill me. So I have no problem fucking around with it, even tho I don’t really know what I am doing.
Reading about it only gave me alot of mixed info, about what spectrums to use. Everyone I talked with, had an oppinon about what spectrum would be best. But when it came down to it, they had only ever tried one or maybe a mix of two.

The same went for 12V vs 24V, everyone have told me 24v is a lot better then 12v due to heat.
And sure that is correct, but how bad is it? Don’t know, never tried!

I then ordered some dual row 12v hard strips, cool white or something. Turned out to be 6500 Kelvin!
Also ordered 24V hard strips, in 3000K, 4000K, 6000K, and 8000K
A bunch of small constant current LED drivers, 30Watt @ 900 ma, 50Watt @ 1500 ma and 70Watt @ 2100 ma.

Biggest issue prolly is the Ebay dealers, don’t have any real datasheets and the little info you get. You really don’t know if you can trust it or not, or if it’s just copied from some where else.
On the other hand, all the stuff I have ordered have been so cheap.
That even tho it might not work, I think it’s worth every penny to do this test and collect this data.

Each test light of 6 strips, have a build cost of less then 40$

Mounted the strips on curtinhanger profile, it was the cheapest alu profile I could find and it was a perfect match!

Cut some old scrap alu profile up, with a hack saw and saved a little money. It seems to be way more alu then needed, but it keeps the frame nice and sturdy.


I use 2x 50 Watt drivers, they are running 24-36 Volt. So I have paired 3x 12V strips up, to split the 36Volt between them. If I knew more about what I am doing, id prolly be able to tell you why it’s only using 40Watt and not 100 watt.
I just trust my digital reading, it says the light and drivers are using 40watt.

So looking at SolStrips and quantum boards, they don’t have a lot of resistors like these do.
What do a resistor do? I think it’s something about limiting the voltage or current, so you don’t fry the LED’s pumping too much juice into them. Look it up if you want to know, don’t take my word for it. I don’t know what I am talking about, im just doing shit. THEY WASTE ENERGY!!!

Again I ask around, what will happen if I remove the resistors of my cheap strips? Most plain and simpley told me not to do that!
Then asked my go to guy, who’s a pro and he told me. That’s not a problem, if you have a datasheet on your LED’s you can just add more of them. Matching up the amount of voltage the resistors lower the strip, so do you have data sheets on the LED’s and resistors?
We already know I don’t, so he too told me. If you do that, blind you risk to fuck it up.

So I did exactly that!

They are brighter then they where before, and it was some spare strips I was shipped by mistake. I ended up getting a refund for, so burning them out will cost nothing.
But so far so good!

Got the lights done, closet somewhat done. With some pink ducktape and fairy dust, I managed to fit it all together.
Fitted some plants into the closet, under the many different spectrums. (Still waiting on a few drivers, so it’s not all strips, that are running on 1500 ma drivers)

A digital PAR meter was too expencive, so we will have to do with 12 organic PAR meters.
I am sure they will show, what spectrums do what for them.

Now I’ll leave it at that, im going on vacation and won’t be back for a couple of weeks.
This should be just the thing they need, a fresh batch of nutes and a big bottle of LITFA.


looking good… being ruled by a garden gnome now! love it


Thank you toasty and yes a little helper is a must!
My old gnome, got himself mixed up with some reggae artists.

So this time around, I got one with a shovel, not a pipe and a light!

Plans of stuff to come, once I get some data and learn a little about the spectrums.
And data I didn’t get in the first post :smiley:

We are at 20-25 Watt/sqft. (everything will be at the wall watt’s)

Once I know how the plants will grow under each spectrum, I will try and mix them up to give me the best veg light possible. Looking at growth speed, internote spacing and overall vigorous health for uniform cuttings.

If im not able to do this, I will increase the watt/sqft until I am happy with it.
As I mentioned I am still waiting on parts, specialy LED drivers.
Once I have had the chance to run the hacked strips, to see if they can handle full current over long periodes.
If it’s a success, I will then try to hack a set of 24V strips, and see if they can handle the abuse or not.

Once I am done with all that, happy with my veg lights.
I will build a flower spectrum light, and collect data on how they preform in flower.
Even tho I don’t plan to flower in the closet, I am sure there are many who would like to see this test done.

Stay tuned, even tho this might take a while!

3 strips on a 70W and 3 strips on a 50W driver

50W driver

70W driver


Damn dude i am digging this thread!! For a “doesn’t know much about” kinda guy it sure as hell fooled me bro. . . When can I start classes?


how are you going to exchange the air in the grow area? gonna get hot in there even with LED.


Good question mate and thanks for stoping by, you too Hoodini!

There is a exhaust point in the top of the closet, with a 5" duct and a small carbon scrubber.
Pulling air from the garage behind the closet, thru a passive 5" intake making it under vacum.
From the closet it moves thru my cooltubes in the flower room and out into the garage attic for now.
Planing on using it, to heat the garage come winter time.

The closet have build in ventilation channels, for hot and cold air that won’t restrict the air flow.
With build in light traps, in case I would wanna flower/make pollen or something. In the top room, it won’t effect or get effected by a different light cycle in the room below.

It’s been the hottest summer here for a long time, and the closet is running a smooth 20-25C degrees.

Grow enviroments im fairly experianced in setting up, getting ventilation right and I have a horticultural degree in hydroponic greenhouse farming. It’s old, but should be valid.

As to my “don’t know much” comment, that is about LED and building electronics.
Seriel and parralel connections and what not, im honestly very confused about it.
But I go about it as if it was LEGO’s, that might break if you put it together wrong.

Soldering and all that, is not hard … okay it’s maybe not super easy, but I got time!


Can’t wait to see all your hard work in action. . . It’s is one of my favorite threads now dude. . . When I finally go to indoors, ima hire you to come hook me up😉


White fabric pots for indoor hydro, I guess I didn’t think that one thru.
They where dirt cheap, I bet I just clicked without really thinking. :smiley:
Repotted 6 of them into black pots, I have more of the black felt pots on the way.

Root’s are looking fine, removed the plastic foil as well.

Good healthy color for the most parts of the plant

Back into the closet they went, I have marked each plant with a kelvin marker.
That way I know where to put them back, when I clean up or what ever reason I would take more then one plant out at a time.

Ec 1.4
pH 5.7


I’m digging the fabric pots with hydro media. Put the pots in trays like a water heater pan. Then can just bottom feed once the roots hit bottom. It’ll be like a super air hempy bucket and it’d take all the guess work out of watering. Oh also with bottom feed no need for flushing n wont waste as much.

1 Like

Thanks, it’s just to try it out. Always been a fan of square pots as they fill out the space, keeping a lot of moms to get more uniform clones.

I acctualy tested automatic fed hempy buckets, many years ago and with perlite and it worked fine.
But it was easyer to keep track of the root’s, when to trim the rootball in hydroton. Not to talke about getting the rootball, out of the buckets of perlite, clean it up enough to trim it.
A much easier job in hydroton, and thats my main concern about the fabric pots. I won’t be able to see if when it’s getting rootbound, and the rootball may expand. To a point where it won’t be as easy, to pull it from the pot.

The bottom have a drain, so bottom feeding in hydroton won’t be a solid option. Drip feeding should give a better nutrient destribution and uptake, and limit salt buildup in the top layer.
Each veg/mom room have a feedline and a bottom drain, that drains to each of their own res at the very bottom.

A felt mat ensures the table drains after end watering, it’s easy to clean once it get’s a little nasty.
I can simply pull it out, into the landery washer and put it back in the closet.

I am not running anything to waste, Normaly I would only change res, once my pH tell me there are a waste nutrient build up. But these are fairly small, so I will prolly top them two or tree times. Ad nutrient with the 2nd toping, and then change everything every 2-3 weeks. Depending on how they are doing.

Thats how I used to do, it worked great. We will see if I forgot all, or I still have some greenthumb in me.

Flowers look tasety, can’t wait to smoke my own again after 10 years!

Cheese at 54 days


Hola Palindrome

Long time Hey

Great set up on the way

I have a uk Cheese outdoor.

Keep up



Hey Barefrog

Yeah it have, sry for the late reply, im on vacation atm.

Will be back in a few days, have to go home and chop some plants.


How about all LED brothers? I am very interested in learning about the different spectra that our plants use, how does the spectra about 630nm work for flowering? in some Spanish forums and been following a grower who potentizes different spectra in the different stadiums of the plants, saturating the far red growing area to make the plant think that autumn has come and that deceives it and makes it produce bigger buds and resin with very high levels of THC and buds that look like rockets


If the tests ends with a better result then HID, I will have no problem making a switch.

I have tested mixed spectrum of HPS and MH for flower, but I ended up just using MH for veg and 1K HPS’ for flower. This was more then 10 years ago, a lot of stuff have clearly happend in the research of growing Cannabis.

In my research on this, I have found different info on different forums. But no sources, or details from their tests.
It might be they arn’t allowed to publish all the data, for some reason or they did and I just haven’t found it.
But in the end I figured, I would just run some simple tests myself. Have some fun collecting data, share it and see what happens.

630 nm should be fine for flowering, but im not running any nm wavelength specific LED’s.
I think there have been done plently, of side by side tests of Burple and White light LED light.
That I feel it safe to say White light LED’s are better, then Burple lights and as I understood they are made from wavelength specific LED’s.

Thats why I run white spectrum LED’s in different Kelvin degrees, they are all sending out a mix of full spectrum light with peak’s in specific nm wavelength.
Been trying out some simple spectrum tests, with a prism to get a visual picture of the lights emitted by the LED’s
Only done a basic test to see if it was possible, havent made any isolated test’s.

No idea what strip this it from, but it gives a good reading. My guess is this is the 6000 or 6500K LED’s, as they are very even in the color.

Where this strip is clearly heavy in the blue spectrum, but also send out light in the rest of the PAR spectrum.

400-520 (V): These are the absolute values for the Vegetative.
520-610 ©: These are the absolute values for the Carotenoid.
610-700 (F): These are the absolute values for the Flowering.
These are the absolute values for the Total PAR region

If changing the spectrum during flower, doing anything I have no idea.
Cannabis is a short day plant, flower is triggerd by long nights and not the color of the light.
I would belive that giving the most optimal spectrum, all the way thru flower will give the best result.
If you have a link, that would be interresting.

It seems that during veg the plants is much less picky, it will use the PAR light available for chlorophyll A and B.
For flower we want the plant to make more then just chlorophyll, carotenoids are used for flavor, colors and prolly lot’s of other stuff.

All that put together, mixed LED’s sure speak for a great grow light.

But is this true for cheap china LED’s?

So far the veg test is looking good


The abuse have begun!

Drivers on the 12V light have been udgraded, from 1500 mA to 2100 mA drivers.
It have made a clear difference in the amount of light, now the question is if the hacked strip can handle the higher current or if they will start failing.

Plan is to take clones later today or tomorrow, still got a single plant left to trim and harvest is done.


Could you please explain this in some detail, I normally run my res without exchanging water for the whole grow cycle
IE; I just top up with ‘grow’ nutrients until flowers start forming and then swap to ‘flower’ nutrients without ever emptying the tank.
What should I be watching out for with the PH to tell me my nutrient mix might be out of balance?

You certainly won’t go short of clones from that setup mate.


I can try, but bear with me it’s many years ago I learned and used this stuff. I’ll do my best to explain it!

When the root’s absorb the nutrient ion’s, they also extrude waste ions they don’t use.
Im not an organic grower and my education is based on ion based nutrients, but it should work the same no matter what on the atom and cell lvl.
Look up Root Ion pump cell’s, for more details on how plants uptain nutrients.

When everything is in check, your roots uptain water and nutrients in the right ballance. The extruded ions will keep the mix stabil, or make your pH go up. Once too much waste nutrients are left in the mix. They will start to lockout other things, and your pH should start to act up before your plants show signs of lockout.

Again this is very simplyfied, bascly cos I can’t remember the chemestry behind it all. I’ll see if I can find my old bioligy books and notes, I used to have some very detailed info and posts on this back at old Overgrow.
But if you look into Excessive potassium buildup, and how it locks out Mg and Ca. You should be able to find detailed info, writen by people who havn’t been out of the game for 10 years.

I might be rememberin wrong, and the pH is suposed to move down, not up. I really should try and find thouse old notes!


Read Teeming with Nutrients for a pretty easy to understand explanation of the process. :+1::seedling:


Thankyou for that. So basically I should start new with the nutrients if the PH starts to move out of the normal.


Looks like a good read, found a free PDF thru google.
Easy understanding, id say that depends on the reader. A basic understanding of bioligy and chemestry will make it alot easyer, but it seems to explain everything from the bottom. And You can just read thru it and it will make sence, as you go along!

The PDF is too big to upload here, but anyone who wanna give that a read and maybe learn something.
Just google ‘Teaming with nutrients free pdf’

Pedro, there is a bit more to it, but yeah thats the idea.

If you read the bottles, most will recomend to change every week. That’s a waste of nutes in my experiance, it’s a indicator that something is wrong. It can also just indicate your Ec is too high and the plants aren’t uptaining the nutes correct. Here a res change would be a waste, compared to topping and fine adjusting it a little.