Needing final advice on my side by side DIY COB vs 315CMH grow

I have decided given the limited space I have to purchase (2) 3'x3'x6' tents. Still deciding between VivoSun, Apollo, Milliard, and IPower. Any input on those would be heavily appreciated as I have never purchased pr grown in a tent, my background has been in basements with HPS/MH lights. I now see DE and CMH has surpassed the results of traditional hps, but are still beaten by these COB setups in GPW and efficiency...

More important than the brand of the tent though, I need help with the specs on the COBs and drivers for the build. I have watched Growmau5 and many others and done upwards of 2 weeks reading through as many threads as possible to catch myself up. I went from wanting to swap over to the Cree CXB3590 to the Citizen 1212 to the Vero29 to most currently the CXM22 from Luminus.

I plan to build out an all COB setup once life allows in my main 12'x10' area. In the past have grown with HPS/MH air cooled hoods. Wife and life have consumed that area with and most of my equipment has been sold off, but I am ready to break my way back into the scene with my limited space. These two tents will be used for my perpetual grow after this comparison grow, so no money will be wasted on those.

How many CXM22's would I need to hit a 900+ PPFD in the 3x3 tent?
Could this be accomplished with a single HLG-320H-C1400B Driver?
If not, what driver solution is recommended?
Would 3500k 90CRI or 3000k 80CRI be my best options or would I be short changing the plant in Veg?
I plan to run over sized passive pin heatsinks btw.

9 Seedlings Day 16-18, 2 clone attempts, and a freshly germinated seed.
Day 17.jpg
GrowersChoice 315 CMH has already been ordered as my seedlings now under a 4 bar T5 will eventually need more juice and I didn't wanna prematurely pull the trigger and be sitting here with the wrong set of COBS and drivers in my hands like a fool. So then I figured why not do a side by side on my new two favorite lighting styles once I do build it.

Any advice on anything I have said would be greatly appreciated. This may be my first post here, but have learned so much from RIU already and thank you all for sharing as much as you have.
 

qballizhere

Well-Known Member
I have decided given the limited space I have to purchase (2) 3'x3'x6' tents. Still deciding between VivoSun, Apollo, Milliard, and IPower. Any input on those would be heavily appreciated as I have never purchased pr grown in a tent, my background has been in basements with HPS/MH lights. I now see DE and CMH has surpassed the results of traditional hps, but are still beaten by these COB setups in GPW and efficiency...

More important than the brand of the tent though, I need help with the specs on the COBs and drivers for the build. I have watched Growmau5 and many others and done upwards of 2 weeks reading through as many threads as possible to catch myself up. I went from wanting to swap over to the Cree CXB3590 to the Citizen 1212 to the Vero29 to most currently the CXM22 from Luminus.

I plan to build out an all COB setup once life allows in my main 12'x10' area. In the past have grown with HPS/MH air cooled hoods. Wife and life have consumed that area with and most of my equipment has been sold off, but I am ready to break my way back into the scene with my limited space. These two tents will be used for my perpetual grow after this comparison grow, so no money will be wasted on those.

How many CXM22's would I need to hit a 900+ PPFD in the 3x3 tent?
Could this be accomplished with a single HLG-320H-C1400B Driver?
If not, what driver solution is recommended?
Would 3500k 90CRI or 3000k 80CRI be my best options or would I be short changing the plant in Veg?
I plan to run over sized passive pin heatsinks btw.

9 Seedlings Day 16-18, 2 clone attempts, and a freshly germinated seed.
View attachment 3915343
GrowersChoice 315 CMH has already been ordered as my seedlings now under a 4 bar T5 will eventually need more juice and I didn't wanna prematurely pull the trigger and be sitting here with the wrong set of COBS and drivers in my hands like a fool. So then I figured why not do a side by side on my new two favorite lighting styles once I do build it.

Any advice on anything I have said would be greatly appreciated. This may be my first post here, but have learned so much from RIU already and thank you all for sharing as much as you have.
I am running the cxm22 3000k and I would suggest 8 in that area and for a driver I would suggest the ELG 240 36 $10-$15 cheaper per driver and put 4 cobs per driver that would put each cob running @ 1.66A
If you want built in software dimming ie sunrise and sunset dimming then look at the elg 240 36d2
The higher kelvin you use in veg the tighter the node stacking will be
 
(2) ELG-240-36D2 to ( 8 ) CXM22 in a 3x3 is what PPFD?
(1) HLG-320H-3 to (6) CXM22 in a 3x3 is what PPFD?

Your suggestion will be higher for sure, I am just curious if that difference will justify the extra total build cost. Anyone know how to crunch those numbers?

Thank you very much for the reply and info on the kelvin and veg growth too. How are you liking your lights?
 

NapalmZen

Well-Known Member
vivosun makes a durable tent. and i mean durable. i have 2 of them and the zippers are massive. i haven't spent much time around others except at grow shops, but what i have seen wouldnt survive daily zipping for a year. the vivosun zipper will last 5-10.
 

qballizhere

Well-Known Member
(2) ELG-240-36D2 to ( 8 ) CXM22 in a 3x3 is what PPFD?
(1) HLG-320H-3 to (6) CXM22 in a 3x3 is what PPFD?

Your suggestion will be higher for sure, I am just curious if that difference will justify the extra total build cost. Anyone know how to crunch those numbers?

Thank you very much for the reply and info on the kelvin and veg growth too. How are you liking your lights?
The lights I love them glad I made the switch from hps and not going to look back.
There is a diy calculator that I have used to get the numbers it doesnt have luminus in it but they are a little more efficient than the citizen 1818
6 cobs @ 1.4A is 1040 ppfd
8 cobs @ 1.4A is 1383 ppfd
having only 6 in a 3 foot area you would have cobs spaced about 10"-12" apart and that is fine I wouldnt go any further apart. I prefer to have them 8"-9" I run a double scrog and I have seen dark shade areas after the stretch but I like to keep the lights close 6-10" from the top. The only time I see leaf burn is when they are within 1" from the reflectors. With the software dimming the drivers are only at 100% 6 hours a day
I will be adding more light to mine just working out how when you have 8 lights plus adding ac because I maxed it out already gets a little challenging since the room is run perpetual and never is completely empty.
Also having the higher ppfd you can take full advantage of adding co2
To me its easier to dim a light if needed than it is to add light if you want more.
 
Day 23-25 Seedlings doing well and I have nailed down the decision on the VivoSun 3x3 tent with 8 CXM22 at 50w each. Gonna scrap the CMH side by side and go all LED for the two tents though. Returned the 315 CMH after doing a bit more thinking on long term costs. The t5's will do fine until they are built I am sure. Thanks for the advice and feedback.
 

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So the tent is setup and the plants have started their new life. Temperature is staying around 74-78 with 38-45% humidity. Using an Amazon Blurple LED leftover from my cousins previous grow as I await my Cobkits shipment.20170409_144401.jpg 20170409_144415.jpg
 
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