PPM seems to work more than fine for you. I have read that commercial growers in BC drop thier PPM real low during the last 2 weeks for potency. I am an evidence based kind of guy and have never seen any emperical data on it, but these guys are highly motivated by profit and a lot of other things that they suggest make sense. I am just curious if you have ever heard or read about this. I have never grown with CO2 enrichment but will be this next time so I have been trying to read up on it. This journal is the closest thing to peer reviewed literature dealing with cannabis cultivation that I have found. I have said it before and i mean it I really appreciate all the hard work you put into to documenting your grows.
I would try altering the CO2 levels at the end like that, but I'm doing perpetual in 3 slots of 2, so I rarely have the whole room synchronized. It would be interesting to see if there is a noticeable difference. I've never heard of the idea. I dunno.
Disclaimer: OK, what follows is my own speculation. I don't know if it is true, but in the model I use to understand the plants, the following has not been proven false. So I use it as truth until I learn otherwise, and it may not be correct at all. If you know that I am right or wrong, let me know. That said...
I believe a high CO2 concentration revs the engine of the plant, as long as you have the light, warmth, water and nutrients to match. A great corollary is that high CO2 enrichment can help the plants survive warmer temps better (thrive even). In this way I try t use the CO2 as a buffer. You see, I try to rev my plants' metabolisms, but I doubt I manage to rev them enough to normally use 1800 ppm, however, if my AC fails and there is no backup, the extra CO2 acts like a buffer. The plants can take a longer period of extreme heat and recover.
[/speculation]
It's worth the extra expense IMO for the extra CO2, even though I buy it by the 50lb cylinder. It's $300 to buy into a tank (I have 2), $26 to exchange an empty for a full cylinder, and in this room 1 cylinder lasts about 14-16 days on average, longer if I keep the
dang door shut. I see closers in my future. Anyways, about $52 per month. High octane fuel and insurance in one. CO2 is a wonder.
love the pictures, you have some really bushy plants in veg. My SLH gets like your Matty, really heavy and can't hold the weight up, it's a shame because I usually just chop them early because I'm too lazy to tie them up
I top veg early usually, then later I clone off the top to produce a flat-ish canopy. That leads to bushy plants, for sure.
Aaaagh!
Another tie-up, is it then? [grumble]
[action report]
==> Bloom - Pre-feed flush (3)
BD.6D (43/70 days) : 0.50 gal
BD.6E (43/70 days) : 0.50 gal
SLH (12/70 days) : 0.25 gal
TDR (12/70 days) : 0.25 gal
MTP.2G (02/70 days) : 0.25 gal
MTP.2H (02/70 days) : 0.25 gal
-Mix (2) gallons
-Per gallon:
1 T liquid steamed bone meal
1 T Yucca
pH target: 6.20 (±.10) Actual: 6.26 @ 20.9 C
1/2 T blackstrap molasses
==> Bloom - Feed (4)
BD.6D : 1.50 gal
BD.6E : 1.50 gal
-Mix (3) gallons - MID
-Per gallon:
1 T liquid steamed bone meal
2 T Biggest Bloom
2 t PGE
1 t Silica Blast
1 t Cal-Mag
1 T Yucca
2 t Notrozyme
2 t Organic Supplement
2 t Soil Nute
--- t Big Foot (ord)
1 t Calcium Syrup
1/2 t Carbon sweet
2 T Amino Blast
1/2 t TM-7
Natural @ 1180 ppm
pH target: 6.20 (±.10) Actual: 6.17 @ 21.1 C
1/2 t Companion
1 t Hygrozyme
SLH : 0.75 gal
TDR : 0.75 gal
MTP.2G : 0.75 gal
MTP.2H : 0.75 gal
-Mix (3) gallons - EARLY
-Per gallon:
1 T liquid steamed bone meal
1 T Biggest Bloom
1 t PGE
1 t Silica Blast
1 t Cal-Mag
1 T Yucca
2 t Notrozyme
2 t Organic Supplement
2 t Soil Nute
--- t Big Foot (ord)
1 t Calcium Syrup
1/2 t Carbon sweet
1 T Amino Blast
1/2 t TM-7
Natural @ 1080 ppm
pH target: 6.20 (±.10) Actual: 6.15 @ 20.9 C
1/2 t Companion
1 t Hygrozyme
==> All Veg (7):
GKA : 0.50 gal
BD.6J, BD.6K : 0.25 gal ea
BBX.3F
L.5Q : 0.25 gal ea
TRN.2C
CH
-Mix (2) gallons
-Per gallon:
1 T Pure Blend Pro Grow
1 t Cal-Mag
1 T Yucca
--- t Big Foot (ord)
--- t TM-7
Natural @ 840 ppm
pH target: 6.20 (±.10) Actual: 6.21 @ 21.1 C
1/2 t Companion
[/action report]