5th Week Disasters

[Dalek]

I have planted 3 crops in the last year or so. In each of these grows, the plants were doing great until about week 5 when pH problems begin to occur, and I can't figure out what I'm doing wrong. I'm using Fox Farm, Happy Frog, nutrient trio by Gen Hydro. From the beginning, I watered or mixed nutrients at pH 6.5. Once I was able to water enough to get runoff, it measured 5.3. So, I began to give the pH 7.0, after 2 weeks, with the plants continuing to worsen, I began to give them pH 8.0. While, I was able to get runoff above 6.0. But, according to Sirius, there is a difference between runoff pH, and the pH of the root zone. He calculates this as pH in minus pH runoff, and subtracting this number from the runoff pH. I have an Aprea pH pen and I calibrate monthly.

What am I doing wrong?

Dale

[Allotrope1000]

Hard to tell without more info and some pics.
May I suggest switching to coco/perlite for your next grow? I use 50/50, GH Trio nutes, pH'd to +/- 6.0. Never had a failed crop.

BTW, I also grow out seedlings into well- rooted 1 gallon plants, then transplant to 7 gallon fabric pots. I do not plant seeds in final pot. I avoid weak seeds. A little extra work to ensure strong, healthy plants.

[golfnrl]

Your runoff PH will rarely be the same as the water going in. As long as it is in the soil PH range you should be good. Since your runoff PH is 5.3 that's too acidic. That's most likely caused from a build up of salts and/or overfeeding. I think you have a couple of options. Let your pot dry out. The first couple of inches should be bone dry. When the pot is dry and light when lifted, water with a very mild nutrient solution or water and cal/mag.

Sounds to me like you probably have a lockout going due to the high PH going in. To address that you can flush your pot with plain Ph'd water at 3x's the volume of the pot. Let your pot drain and then water it in with a mild nutrient solution and let the pot drain.

If you are not sure about flushing your plants, start with letting the pot dry out first.

Put up some pics if you can.

Are these the same plants as those in the thread?

https://forum.growweedeasy.com/forum/growing-community/666544-ph-problems-during-early-flowering

[Ckbrew]

Agree with Allotrope, try coco/p hard to go wrong.