Midflower pH Issues
- Thread starter SoCal Calyx
- Start date
Southerner
Well-Known Member
Interesting. What pot size are you using? I find the bigger the better with organic soil if your trying to get some numbers. I end up using 7s because I like having a lot of variety, but if I was looking for more yield I’d bump up to 15s or so. With hydro, it’s a way different story.
ShLUbY
Well-Known Member
didn't matter the pot size, it was happening from 5 gal all the way to my 20 gal no tills. I had recycled the soil so many times and oversaturated them with compost. peat lost its acidic effect. went back to a fresh mix, pH is back to normal and so are yields. I was just adding too much compost during recycles. i'll probably only be doing it every 3rd run or so now.
SoCal Calyx
Active Member
Thanks for the responses guys, I really appreciate it.
@ShLUbY you mentioned the pH of your RO and the addition of air. That got me thinking about my RO reservoir. The pH of my tap water is about 8.5, running it through the RO system brings it down around 7.5. But I hadn't checked the pH of the RO water in the rez in a few months. When I checked it things got more interesting...the pH was over 9!
This got me checking things out further within the rez and RO system. I've been using one of those black 8 gallon square buckets and lid, the same type the RDWC guys use, for my RO rez. I figured it was fine b/c it was black, well the inside walls had a thin slime built up on them. Looking closer at the RO system I realized that it had small areas of algae growing in the filter canisters (they're clear for god knows what reason). I should have been more cautious of all this from my years in hydro last decade. Noob move.
So this likely explains why the pH in these containers was steadily increasing and the unused soil of the same mix was not. The unused soil hasn't got much of this bad RO water at all since it's housed in my compost tumbler and stays consistently moist on its own. I typically only water it with left over compost teas which likely have settled in pH after all the brew activity.
What's even more interesting is that all my worry over yield sure seem to be for nothing. These plants are stacking very well considering everything. Here they are at 31 days...
I guess the cannabis gods must be smiling on me this go around. My plan now is to pull the RO filters, flush the system with diluted hydrogen peroxide, change the filters and clean/sanitize the rez and refill with fresh RO.
I'm going to add an air stone to this rez too and see where that puts my pH. Thanks again for all the feedback, I'm learning so much on this organic soil side of things but have so much more to learn.
@ShLUbY you mentioned the pH of your RO and the addition of air. That got me thinking about my RO reservoir. The pH of my tap water is about 8.5, running it through the RO system brings it down around 7.5. But I hadn't checked the pH of the RO water in the rez in a few months. When I checked it things got more interesting...the pH was over 9!
This got me checking things out further within the rez and RO system. I've been using one of those black 8 gallon square buckets and lid, the same type the RDWC guys use, for my RO rez. I figured it was fine b/c it was black, well the inside walls had a thin slime built up on them. Looking closer at the RO system I realized that it had small areas of algae growing in the filter canisters (they're clear for god knows what reason). I should have been more cautious of all this from my years in hydro last decade. Noob move.
So this likely explains why the pH in these containers was steadily increasing and the unused soil of the same mix was not. The unused soil hasn't got much of this bad RO water at all since it's housed in my compost tumbler and stays consistently moist on its own. I typically only water it with left over compost teas which likely have settled in pH after all the brew activity.
What's even more interesting is that all my worry over yield sure seem to be for nothing. These plants are stacking very well considering everything. Here they are at 31 days...
I guess the cannabis gods must be smiling on me this go around. My plan now is to pull the RO filters, flush the system with diluted hydrogen peroxide, change the filters and clean/sanitize the rez and refill with fresh RO.
I'm going to add an air stone to this rez too and see where that puts my pH. Thanks again for all the feedback, I'm learning so much on this organic soil side of things but have so much more to learn.
Last edited:
SoCal Calyx
Active Member
Oh that reminds me, do you all know if brewing sanitizer (Star San) is ok to use in place of bleach for sanitizing grow equipment? I hate using bleach b/c of the film it leaves behind. I figure brewing sanitizer would be a good option b/c it's designed to be clear rinsing as not to leave behind anything that might screw with the brewing process.
ShLUbY
Well-Known Member
sounds like a good option to me. i just use dish soap to clean stuff and make sure i rinse it away real well.
I'm glad we helped you pinpoint something that can be improved upon! plants look great man. keep it up