You can do a soil slurry to get accurate soil readings. Take soil sample from 2 or more inches under top soil and mix with equal parts distilled water ( i.e- 1 tbls water : 1 tbls soil) aggitate for 1 min allow to sit for 15 mins then do ph and tds on solution) this will tell you exactly where your soil sits.
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I do it on occasion. Should do it more often.
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Dang – I love this little chart.
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Improved #s today. Upped the ingoing pH when watering to 6.7. Same pH coming out with much improved ppm#s. Checked the five plants I was concerned about. With 45 ppms going in I got runoff between 1000 and 2200.
Thanks everyone. Another lesson being taught and I hope learned (by me).
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I read that water with a tds under 250 will not hold its own ph.
Now Y’all got me thinkin…good grief
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I’m not sure what you mean… more info?
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It never ends right? Just when I think I’m getting it together – BAM – some other factor or unknown element shows up. 
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Water with less then 250 parts per million (ppm) total disolved solids (tds) wont hold its own ph.
So lets say you have a standard glass of RO water. With your tds meter you read it as 45ppm and with your ph pen it reads 8.5ph. Too high right? Use ph down get her to 6.8. No matter what you do to ph that water because it has less then 250 part per million total dissolved solids it wont hold that ph. You pour it into the soil and instead of adjusting the ph of the soil the water will instead adopt the ph of the soil which can cause lock out, its the reverse of feeding too much nutes and tanking the ph of your soil. To avoid this, I will use calmag only on water days and no calmag on feed days.
Did I make better sense?
When doing a soil flush, I always make the last gallon ph stable water then full feed after that. Seems to work well for me.
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I’ve been using CalMag about every other water or so. With CM, I should pH water first then add the CalMag and then not adjust pH again, right?
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No. You add the cal mag then ph liquid. Same with all nutes.
Also if using RO water, LED lights, or both will need calmag every other watering for sure.
I use my tap water which is 7.2 pH (most of the time) with about 45 ppms. I do use LED lights. I’m running autos in FFHF + FFOF + Pearlite on a 24/0 light schedule.
Of course I pH the water after any nutes. Just not real familiar with CalMag yet – but using it.
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Your tap water only has 45 ppm dissolved solids?? Thats awesome water! My tap water is 450ppm dissolved solids and smells like swimming pool water… Shit my RO water has more then 45ppm.
Your tap water is not ph stable. It reads 7.2 outta the faucet but as soon as you pour it into the soil the waters ph becomes the soils ph instead of what you want which is to adjust the soils ph to that of the liquid you have poured into it.
You should let them sleep some, 18/6 will be better for your pocket book and better for your plants.
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I’m just afraid of 18/6 for autos – unreasonable I know. I’m going to go to a 20/4 schedule for the summer.
Some processes only happen in the dark. I read somewhere that thc production/maturation occurs during lights out. Take humans for example. We only produce the chemicals that clean our brains when we sleep. If our brains arent flushed clean the toxins build and we go crazy. Literal insanity from sleep deprivation.
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Im listenin….and laughin.
@GrnyGrows I started my autos when I flipped Black Widows to 12/12. They’re not doin too bad. More for shits n giggles. This ph stuff got me scratchin my head again. 6.0-6.1 goin in
5.95-6.0 out. All good right ?? Ppm has been 1200ish on bushy girl, 1700 on big plant.
All good right ?? @Docnraq
7th and 8th week actual flower. Soil. Jacks. ??
Got my bags yesterday.
No sticker. Jerks.
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I’m stickerless too. I think your numbers are good. I just realized the reason my ppms might have been so high – I think I put the CalMag in and forgot to pH the water. Oh the toils of we growers.
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Plants look healthy. Painted nails, a little heat stress curl , otherwise no issues. Im pushin em. Sunday will be 8 weeks actual flower for the big plant. Smaller is 10 days behind. Autos were born on 4/2…
Comin down the home stretch !!
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Kinda low for soil. I always go in @ 6.8ph no matter what im putting in. This has worked well for me. Ive read that you want to fluctuate based on runoff readings to nail that 6.5 ph during flower but 6.8 in has become the regular for me.
Kinda low for soil. 6-6.8 is what you wanna shoot for 6.5 is just the sweetspot. See chart below. Note that Phos best uptake begins at 6.5ph it can uptake some at lower ph but for flowering, you want that phos.
This would depend on growth stage plant type genetics and over all plant health. I use FFOF cut with like 30 percent perlite. First full watering will give me a runoff around 2k ppm or more depending. I begin to feed when the runoff gets to around 800ppm and start slow like 1/4 strength first time. Then increase depending on reactions and runoff readings. When flowering hits I increase the concentration of nutes till runoff of about 1000 ppm until after transition then I try to keep around 1500 until last few weeks, where I only give straight ro water un ph’d.
Ive never used Jacks. Only FF trio and FF PK boosters.
You may wish to reset your soil. If you flush out all that you have put in, possibly incorrectly. You can then feed and reset the ph and ppm of your medium.
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