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Building a COB style LED

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#61 kcmoxtractor


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Posted 14 August 2016 - 08:12 PM

round 3, today makes 7 days flowering. i will let them get to 14 days

then strip off everything inside and below the trellis. 



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#62 Hash_Man


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Posted 18 August 2016 - 05:54 AM

That is what I was after. Thanks kcmoxtractor. Learning a lot on this, as I think these COB LED's are really going to be the future of growing. Hell, the efficiency alone is making me debate skipping over buying some 600w HIDs for significantly cheaper just because I know in a years time, they'll save their cost alone, not to mention the revenue that can be generated.
Here's to hoping you win that contest! Good luck!
Aside from digikey, are there any other suppliers available for the COB LEDs? Google offered very little aside from a bunch of electrical specs.

Right now digikey has 3500k's for 32.00

#63 kcmoxtractor


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Posted 10 January 2017 - 04:38 PM

Been a while, but these fixtures are still killin' it with zero maintenance

or extra costs beyond the initial build. 


i've greatly simplified my routine as well, by switching to jack's tomato feED.


for months i tried to figure out a soil mixture that would supply the plant with 

enough nutrition so that i could just add RO water, and i couldn't find such 

a mix. now i'm just doing coco coir, growstones, worm castings, a mineral

powder mix, kelp, alfalfa, and bone meal, and using water solubles. i went over to

a local plant nursery and checked out their dry fertilizer salts section, and they

had some jack's tomato feED, $10 for 1.5 lbs. picked up a tub and i have to say,

it's the best fertilizer i've ever used, hands down. here's the recipe i use for it-


3 gallons distilled or RO water

1 gallon of hot tap water (360ppm)

1 pint hot tap water (360 ppm)

1 tbsp tomato feed

1 tsp epsom salt


dump 3 gallons of distilled or RO into a bucket


dissolve 1 tsp of epsom salt into the pint of hot water, dump the pint of dissolved

epsom into the bucket


dissolve the tbsp of tomato feed into the gallon of hot water, then dump into

the bucket. it's best to add the nutrients to the hot water, give it a good shake,

then come back after 5 minutes and shake again before mixing into the bucket. 


i use that ratio of tap water to distilled or RO so i can hit ~100 ppm of calcium in 

the final solution. i use epsom salts to add magnesium and sulfur, and 






few new varieties, krome's the white








king louis og




group shots






btk kush from last round, these were just coco, castings, and growstones 

for the medium and fed with drippers. yield was crazy high, this total round 

should be 23-24 oz from 455w. 









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#64 Hash_Man


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Posted 10 January 2017 - 06:17 PM

To say, 'really nice' be an understatement
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#65 Heirloom Spores

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Posted 11 January 2017 - 12:32 PM

Inspiring, a great yield for the watts. Beautiful.

#66 kcmoxtractor


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Posted 11 January 2017 - 03:40 PM

here's the second space, it had a problem in early flowering with thrips and

gnats. used a pyrethrin and sulfur spray that seemed to knock the thrips out

pretty well. used a diatomaceous earth top dressing for the gnats, but they 

came back a bit after a few weeks. it's easy to over apply DE as a top dressing

and it takes forever to water, definitely best applying small amounts daily or

every other day for a few week period IMO.  


this tent is a 2x4 with 200w of 3500k bridgelux vero gen7 COBs. should be 

about 50% efficiency for the chips, gen7 really caught up with cree's CXB. 


strains are larry's OG and west coast sour diesel. i'm hoping to still hit g/w

even though i had a pest problem. pictures are at 50 days


group shots, the taller three in the middle with some coloration are larry. 






west coast sour D






larry's OG





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#67 Myc


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Posted 11 January 2017 - 04:59 PM

I use the "scorched earth" strategy for Thrips and Spider Mites.


Harvest, burn, shut off the lights and let things go cold for a year. 

Bugs make me so effing mad.........and the only time I ever get them is when I don't perform quarantine protocol. When receiving genetics from friends - place your cultivars in a sealed glovebox (I'm serious). Take soil samples and water samples - perform microscopy. Examine canopy and vegetative structure - in the nodes and under the leaves. Let the cultivars stay in the sealed glovebox for two weeks minimum. Repeat performance of samples and microscopy.  

Better yet, tell your friend "Thanks, but no thanks." I realize that at times this can be an irresistible proposition - you'll learn eventually (see above). 


Spider Mites were the last invader. After 14 months, they should be thoroughly dead. I hope they starved a horrible, nasty demise and roast somewhere in arachnoid hell. 

Should I accept some cuttings from a friend to get started? (LOL trick question alert.)

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#68 kcmoxtractor


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Posted 11 January 2017 - 06:51 PM

i actually got spider mites from a rose i bought at lowes, and the thrips either caught

a ride from the commercial food processing place (they do thousands of pounds of

cole slaw a week and cabbage is notorious for thrips), or from the kale in our garden,

they could have hitched in on me or the dogs. that's the disadvantage of having a 

bio diverse yard and 1000 sq ft of raised beds, if you get a pest outside it balances 

itself out, but the predator might not hitch a ride indoors with the prey. 


i don't really care very much about gnats, they seem unavoidable (without a dedicated

facility and lots of safeguards in place) in an indoor grow in my part of the USA. 


it's hard for me to say no to clones that pull 1.5 g/w at 30%+ potency. i've been working

on changing my outlook on pest control and favoring prevention instead of treatment. 

when i didn't have pets, a garden, or a yard to care for i never had issues, so i hadn't 

developed a routine for preventing insects. 


regularly spraying plants to prevent insects is easier than constant inspection of surfaces

and medium. i found it's best to use a rotation of vegetable oil, dr earth final stop (copy

and pasted from their site- Rosemary Oil, Sesame Oil, Peppermint Oil, Thyme Oil, Cinnamon

Oil, and Garlic Oil, Beeswax, Carrageenan, Cellulose, Citric Acid, Glycerin, Lecithin, and Water),

neem oil, and the sulfur/pyrethrin combo spray, but only use the pyrethrin every other rotation. we

use a biodegradable soap to emulsify the oil products (vegetable, dr earth, neem) and i

feel like that made a big difference in their effectiveness. as long as i stayed on this routine, 

i never had bugs.. if i fuck up and don't follow my rules, stuff like that ^^ happens. 


when my rooms finish (even on the perpetual room) i always pull everything out, spray 

the walls, floors, corners, and every other nook and cranny with bleach, and scrub

the bejeesus out of all surfaces. 

Edited by kcmoxtractor, 11 January 2017 - 06:52 PM.

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