DIYers try to recreate CREE vs Gravita?

MeGaKiLlErMaN

Well-Known Member
Diminishing returns increases at any two points in a PPFD chart. People need to examine whether it's worth the extra juice to squeeze out a few more grams. My experience with sub 800 PPFD has been very good, on the order of 55-60 g/ft. Bumping the levels up to 1000 doesn't present a challenge to the plants but going over 1300 can begin to be problematic. The yield difference between 1300 and 1500 is likely negligible even under ideal circumstances. People have recently been planning 1800 and 2000+ PPFDs. I don't see the point from a practical perspective but there's useful field data to be had on the order of "this is why you don't do this". I say bring it on... but I wouldn't recommend it. My ideal system would be capable of 1200-1300 PPFD with the ability to dim. I would be happy with 1000 PPFD, something I never even grew with.
Unless you plan for light degradation over the distance of penetration while getting way deeper than HPS would ever dream. Removing alot of fan leafs of course and allowing light to come through, Or at the very least letting you have your lights higher.
 

MeGaKiLlErMaN

Well-Known Member
and your massive airflow that keeps em breathing



1500 is hard to master even
No doubt, but without worrying about canopy temps much its cant be that hard if you have a basic CO2 setup. 1200PPFD was a breeze... Though I do have one note on this since I ran a very blue light. Raise the light and let the plant stretch... that is all.
 

MeGaKiLlErMaN

Well-Known Member
I think with the addition of CO2 at 1500ppm you could achieve 2000 umol but like @sixstring2112 said monitoring everything may become a challenge.
Doubt this would be possible in veg tho with DLI climbing too high. Looks like the graph is still rising at 1000ppm.




There are way too many graphs for CO2 and PPFD but if you were to go by this a a few other aspects you could find the sweet spot for growing, like 86F 65RH 1500PPFD and 1000-1200PPM CO2
 

Rider509

Well-Known Member
There are way too many graphs for CO2 and PPFD but if you were to go by this a a few other aspects you could find the sweet spot for growing, like 86F 65RH 1500PPFD and 1000-1200PPM CO2
You've just described my grow! LOL

J/k. I have no idea what my PPFD is. I'm running 35K 80CRI 3590s at up to 80W each with one COB/ft2, dimmed back during veg. But the temp, humidity, and CO2 are spot on in my grow.
 
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I think I got just what this thread is looking for, built one over the winter with the exception of different heat sink (heatsink USA) and enermax quiet fans. Very expensive build, kind and Mars charge 2500 for you can build one for Around 1000 bucks. Curious how well it does? Me too
Quite the work to build one too. If anyone's interested I'll start a grow diary with a six plant legal grow
 

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MeGaKiLlErMaN

Well-Known Member
I think I got just what this thread is looking for, built one over the winter with the exception of different heat sink (heatsink USA) and enermax quiet fans. Very expensive build, kind and Mars charge 2500 for you can build one for Around 1000 bucks. Curious how well it does? Me too
Quite the work to build one too. If anyone's interested I'll start a grow diary with a six plant legal grow
I would check it out. Make a new post giving all the details when you have time
 

nogod_

Well-Known Member
Stoked to see it in action...

Go ez on the box wine when you're hooking everything up!

I think I got just what this thread is looking for, built one over the winter with the exception of different heat sink (heatsink USA) and enermax quiet fans. Very expensive build, kind and Mars charge 2500 for you can build one for Around 1000 bucks. Curious how well it does? Me too
Quite the work to build one too. If anyone's interested I'll start a grow diary with a six plant legal grow
 

Rider509

Well-Known Member
I'm doing the same thing but running 4 3590s per 320H-C2100B. It gives me the flexibility to bang out 75W per COB at 2100ma if I want, although they're usually cruising along at 48W per at 1400ma.
 

REALSTYLES

Well-Known Member
Most of my plants are almost 4' tall and only 8 in a 4x8 tent. Oh yeah almost forgot I'm running 2400w in that tent lol. Will destroy Gavitas

 

AliCakes

Well-Known Member
Okay, guys. I've watched hours of YouTube and read through a few very technical threads since I made this post. In some ways, I feel dumber than when I started....but I think I have a basic design in mind.

We are thinking 2 lights in our 4x4 tent something like the picture below. Passive pin heat sinks on the cobs. (Cxb3590s 4000k) And then XPEs on extruded bar heat sinks in between. When looking at the spectrum graphs, it seems that Photo Reds (~670nm) is the most lacking, but how many do you think I need to add per 6 cob fixture and why? Same with the reds, far reds, etc?

As I have said before. Prior to the last three years, I do have a good deal of indoor growing experience, but my one and only LED was a blurple Lighthouse hydro. We can afford it now, so we definitely wanted to up the game this time around.

I have a 600 w HPS, but I live in Texas and want to up the game without adding a bunch of extra heat.

I do welcome any constructive criticism on my design.... especially now, when I haven't pulled out the credit card just yet.1493492290132374965524.jpg
 
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