Re: CO2 rate
There are a few ways to get things cooking.
1.Less light in the start up phase, 1.5-2w/gal
2. Add CO2 on another timer, starting 1/2- to 1 hour prior to lights on.
3. More current(unless maxed out already)/mixing
4. Less plant biomass(eg low growing HC mostly)
5. Distribution and flow pattern adjustments
Even if you max out all these, 15ppm at the one hour mark start, then gradually up to 30ppm at 2-3 hours is likely fine.
Main thing is to prevent CO2 limiting conditions. There are a few ways to do that.
I think mist method is one such method.
I see large growth rates eariler in the day using that method with similar or even lower CO2 ppm in the water.
This was confirmed by measuring the DO levels.
The plants, more so than the CO2 ppm, is the main focus.
The CO2 maybe a secondary effect, even if the CO2 is only 10ppm dissolved, how much is getting to the weeds that first 1-2 hours as mist?
I do not know, but I do know the O2 levels rise much faster.
So something is occuring, whether folks believe my notions or not I really no longer care.
Same thing with the venturi mist internal reactors.
You can max those out early in the day and then back off the flow(DIY can even be used in conjunction with gas tanks or a dual solenoid/valve to add more CO2 during the initial 1-2 hour phase).
Regards,
Tom Barr
Regards,
Tom Barr