Issues with root pH. Help would be greatly apreciated!

[Stylee22]

Hey everyone,

I’m having a real tough time maintaining proper pH at the roots (Im about to go crazy trying to figure this out). Here’s a quick rundown on my setup.
Indoor tent, well ventilated, 600w HPS, humidity and temp always monitored and between 40-60% and 72-79F respectively.
Fox Farm OF soil. I use grow bag/fabric pots and transition from 1gal-3gal-5gal all in veg. I finish them in 5gal through flower.
Fertilize with Fox Farm trio 1/2 strength what they recommend every 3rd wattering. I start fertilizing about 3 weeks after transplant. I sedgehammer flush every 4-6weeks.
If not fertlizing i use tap water and carefully always check my pH which is where my problem is. I used to water with pH around 6.5 then 7.0 and now im putting in 7.4 and the runoff is still acidic. No matter what the f*** I seem to put in my pH run off is always low. Its really hard for me to get it anywhere above 6.0. Plants look amazing until about a month into flowering then they start showing cal/mag deficiency which im assuming is a pH issue. Flushing 3x pot size with pH 7 water does not seem to make a signifciant difference.
I follow watering practices as recommended by growweedeasy.com. Water every 3 days. Enough water to yield 20% runoff.
What the heck am I doing wrong. Do i need to wait before measuring the pH of my tap water after coming from tap? Does it coem out of tap artificially high because of turbulence or something dumb like that?

Thanks

[SoOrbudgal]

Hello there i would like to ask since you've asked the questions of why things are not going well. How come you transplant so often? Most do from solo cup to final pot. It just seems like you do too many steps and you don't need to. Why fertilize? FFOF has stuff that's feeding the plants and it may be too hot for seedlings? I'm thinking you maybe over doing with the ferts.

Keep it really simple they just want light fluffy soil in the beginning and good water. I don't fuss much make issues i've found. Once i get the seed to germinate i stick it in a little 3x3 seedling pot leave it till it grows under a CFL for 2-3wks and do the final transplant into the same type soil light fluffy well draining soil. I don't feed my photos till wk 4 if and that's IF they look like they need it. Me personally do not measure my pH as my plants have been healthy with my well water. I've grown for so many years if i get a little spot or tip burn i know what it's from. Try the less is more method. Keep trying

[Stylee22]

I was under impression transplanting was just best method to keep roots healthy and avoid watering issues but I can definitely go from solo cup to 5gal... would def be easier. I also thought that after 2-3 weeks of normal watering, even FFOFOF will need added nutrients. I only use 1/2 strength FF recommends and only feed every 3rd watering. I use happy frog for seedlings then FFOF when I transplant into bigger pots. I never have any issues in veg, perfect leaves, not even tip burn. All my problems happen with about 1 month left till harvest and almost always look like a calcium or mag deficiency. Just really frustrating everything is great until right at the end and the only thing I can see might be the problem is my pH runoff is usually 5.7

[PRIMO]

It seems to me that watering a 5 gal. pot to runoff every three days is a bit much. Try letting them dry out and get some air to the roots.

[buds73]

Hi, from what I've read on the forum here from others using FFOF it's seems its normal to have a runoff of 5.5 - 5.8 using that soil. You mention you flush every 4-6 wks, you could be washing the nutes in the soil down the drain doing that. Do you allow your water to sit for 24hrs before watering? This helps remove any chlorine (but not cloramine) in the water that can be harmful to micro organisms in the soil. If I were you I wouldn't worry about runoff PH but concentrate more on PH of water going in. 7.4 I think is too high you should try watering between 6 - 7 PH. If you don't already try adding some calmag if you think you have calcium/magnesium difficiencies. Bear in mind you may get some yellowing of lower leaves during flowering and this is normal.

[HobbitGDF]

Listen man, I've had same exact issues. Using same stuff. I have learned that like he just said, focus on what's going in, I dont even do runoff that much anymore.
also with foxfarms nutrients I have to add cal-mag or a month into/before whatever I experience same stuff.
My runoff is always 4.5-5 8 , so I quit checking it and just check what goes in. 6-7 I usually try 6.6


So what they said. It helps

[OlderNOTwiser]

Welcome aboard Stylee22 This whole thing of growing can be confusing as hell can't it? I've read your post many times and I'm going to guess you have very little experience (if any) growing anything previously. So let's keep it simple. First off, we can't see the plant or plants in question so you need to provide us with that asap. Are there actual issues with the plant(s) or is it just overload of information that you want so much to be successful that you're obsessing over every minor detail? Don't take offense, I was exactly at that spot a year ago. I've grown a bunch of stuff over the last half century but these things are a bit different.

I use FFOF myself with the trio. As SoOrbudgal points out above reduce the transplanting (unless it REALLY has outgrown the pot). That's done and in the past so can't change that right now.

Look at this chart for a moment: https://www.growweedeasy.com/wp-cont...-marijuana.jpg At the bottom it mentions root zone pH. Ignore that description and read it as the gospel of what pH you need to be at going in. The plant will use what it needs/wants at these pH levels that you provide. What it leaves behind will no longer be at the pH you provided. When you water to runoff the remnants are what get pushed out and replaced. You're measuring that and it will always be different than your nutes/water. I chased my tail last year with runoff and finally realized I wasn't keeping it simple anymore. I was providing everything the plant needed and the right ratios and it was a beast. Obsessing over runoff wasn't relevant. This week I checked runoff on one plant (first time in a year and because there is an actual issue to be diagnosed) showing root issues. Very acidic so I checked my others and they were identical. And again, if you aren't trying to diagnose or resolve an issue then concentrate on getting the solution to the mid 6 range. It should fluctuate in that area, not important to be exact every time but it does have to be in the range on the chart.

You mention a watering "schedule". So many newer growers get fixated on a schedule. Again, keep it simple. If you can reach your pots comfortably give them a lift. Is it light? Does it feel heavier near the top or bottom? Did you try to stick a finger in the top of the soil to see how deep the moisture is? If the soil is still moist (not wet) at that depth let it ride another day. If the pot is light then water. The only relevant schedule is the one the plant provides to you.

Are you following this chart or similar? https://foxfarm.com/feeding-schedules scroll to soil chart. The whole sledgehammer/flush every few weeks isn't for you at the rates you mention. It is to remove an accumulation of what the plant no longer needs/wants or can't use. The Ocean Forest should get you through about 6 weeks before adding nutes. That is of course dependent on the plant. Heavy feeder and growing strong would be shorter where a tiny sipper could go longer. At this point you've flushed all of the original stuff from the soil so you need the nutes. But again...keep it simple. Not every watering needs to be to big runoff especially at the low rates of nutes you're using. Why are you using nutes every third watering? Were the plants telling you something or did you read it? Again...simple. At 1/2 dosage or even a touch more or less you can easily do every other watering and water to runoff once a week or two. Again simple, but the plant will tell you what it is up to.

I can't overemphasize the importance of pH. The chart says it all. And the water only watering must also be in the mid-6 range. Ignore the runoff for now unless there is an actual issue. Skip the sledghammer unless there is a nutrient lockout or bugs that need flushing. Keep it simple. It's a weed after all and it will grow like one with only a little care.

[9fingerleafs]

You need to use more big bloom (rises ph and contains the calcium) to provide enough nutrients. For the ph issue the key it’s the ppm. The nutrients in the soil are acidic and there’s a lot of them, they dissolve into the water when you water lowering the over all ph. Tap water itself has too little ppms so it doesn’t change the over all ph. What you need is to give high ppm water phed to a higher ph. If your run off is 5.5 it’s a whole unit below 6.5 so you water high ppm at 7.5 or 8 and repeat until the runoff is closer to 6.5. It will take a few waterings to balance but using only tap water you never going to make it happen

[Rwise]

I like things to be simple, I use pelleted sulfur (PH down) and pelleted dolomite (lime)(PH up) to control PH. The plant will move some elements around and fix the soil to what it likes.