Shape Shifter
Well-Known Member
The people at Promix say 5.5-6.0pH is ideal with Promix HP. Some people use 6-6.5pH and get good results. I try to keep it 5.8-6.2pH.
Ph of water going into promix HP please help!
- Thread starter Tommy125
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Growyourownmeds
Active Member
Stay at 6.0 and your fine.
Shape Shifter
Well-Known Member
How much and how often do you feed in veg? 1-1.5L per plant every third day seems to be working for me. I get good runoff. The media retains a minimum amount of moisture well.
I agree with the 5.8-6.2. I used Promix HP for years before switching to Sunshine #4, for which the pH range is the same.
Yes the ideal ph of the medium is 5.5 to 6.0. But the irrigation feedings and plain water do not have to match that. I spoke with Troy Buechel at promix, and he said if your water is of low alkalinity( not to be confused with ph or alkaline) alkalinity is the presence of calcium bicarbonate measured in ppm. Then no ph adjustment is required. My well water is 8.0 ph with 40 ppm alkalinity. When I add nutes it drops to 6.5 ish. On days where I only irrigate with plain water, I do not use ph down. I am currently testing this out and having great results.
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This article goes more in depth about water alkalinity and how it can raise growing medium ph over time.
It is about the growing media. Here is a document that might interest you: http://www.nurserycropscience.info/water/source-water-quality/other-references/substrate-ph-and-water-quality.pdf
It is about the growing media. Here is a document that might interest you: http://www.nurserycropscience.info/water/source-water-quality/other-references/substrate-ph-and-water-quality.pdf
Boatguy
Well-Known Member
Thank you, that article is a little more user friendly haha
Swarmxking
Well-Known Member
Promix hp water between 6.0 to 7.0 always
No run off
Never check ec or runoff ph
Shape Shifter
Well-Known Member
The article can be misleading because lowering the pH with acid lowers the bicarbonate.
What is your ph control like in promix? I started looking into ph deeper when I got problems mid flower. I was adding quite a bit of acid to get the water down to 5.6 to 6.2, which neutralized all alkalinity and caused some weird ph issues. I stopped using ph down for the last 40 days of flower and got the densest, largest harvest I’ve had yet. Currently trying the full cycle with no ph adjustment.
Beauty, do you use RO water, city tap water or well?
What nutrients do you use? Do you feed nutrients on every irrigation?
In coco or peat, you should use nutrients every time you water.
Wouldn’t you get quite a bit of salt build up and nute burn if you fed every irrigation? I use gh flora nutrient schedule. Which suggests to use plain water after after 2-3 feeds. Or do you lower the nutrient concentration so you can feed every time.
I don't get buildup at all. I've been growing the same way in the same medium (started with Promix HP for six or so years, switched to Sunshine #4 a couple of years ago) for a long time, and never had a problem.
I used GH Flora for all those years up until this April when I switched (for control and monetary purposes). I did not do a plain water flush in between. I never check runoff pH. Most of the time I have but a few drops of runoff.
My nutrient solution is a consistent 750-850 PPM veg, slightly higher for flower. Freshly rooted clones and all other veg plants get the same dose. Seedlings I dilute by 50%.
I’ve had a suspicion that I was under feeding. What size pots do you finish in? Did you follow the gh schedule for drain to waste? I finish in 3 gal pots I went on a feed, feed, feed, plain water schedule. Never more than 600 ppm in flower. I still had burnt tips from that and wasn’t sure if I was over or under feeding. I think it was a combo of underfeeding and adding a lot of acid to the mix. At this time I was only using the 3 part. Do you use the entire line?
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I veg for eight weeks. I move my plants from their 1/2 gallon starter pots to the 3 gallon final pots during week 3 or 4 of veg.
I just ran downstairs and grabbed a bottle that has some GH Flora in it. I would have been using marginally under the full amount for the peak veg and flower recommendation. I do not recall what the PPM was, as once I got it dialed in originally (years and years ago), I just repeated the same process, never having to check PPM again.
600 PPM is definitely low for flowering.
What acid were you adding, and why? pH down?
This is the chart I have been following with just the 3 part. https://gh.growgh.com/docs/Feedcharts/GH_FloraSeries-DTW_03216am.pdf
My well water ph is 8.0 and with fert added it drops to 6.5 ish. I would then add acid until it was at around 5.8. It was plant ph down from Canadian tire. Did you use the 3 part alone or did you use their other products?
My well water ph is 8.0 and with fert added it drops to 6.5 ish. I would then add acid until it was at around 5.8. It was plant ph down from Canadian tire. Did you use the 3 part alone or did you use their other products?