Ph lockout in autopot

[Smokeee]

Hi all I’m in need of some advice. I have about 4-5 grows under my belt all in soil. I recently switched over to autopots as im away for work most of the week and they seemed a much simpler way to grow. I’m about 7 weeks into flower. During week 6 I noticed my ph range crept really high up over 8.3 at the rez. I have monitored it since and regular ph’d down within the ideal range. I knew nothing about ph fluctuations in these things…lesson learned. Since then growth has been really slow and i have starting seeing yellowing and rust spots on my leaves. I’m pretty sure I have some ph lockout. My question is how to fix this. They will flower for about 10 weeks and I want to flush and then go back to adding nutes to finish the grow long as they recover. Thing is ive read a bunch of conflicting info on how to flush these things. My grow medium is soil + perlite mix as recommended by autopot and im using ph stable clay pebbles as well. Water source is from the tap. Whats the best way to flush? Should i empty the rez and flush for a week with florakeen or turn off flow from the rez clean the tray and add ph’d water to that and let the plants drink that up and then slowly into nutes again?

 

[Smokeee]

critical XL auto

Mimosa

purple haze auto

Wedding cake ( this and mimosa seem to be refusing to fatten)

 

[Mañ'O'Green]

@Smokeee Welcome to AFN Judging by the looks of your plants (dark forest green) they are getting too much Nitrogen locking out the Potassium. PH can be a problem in all forms of hydroponics but the first sign is usually a Calcium problem and not K which is what I am seeing.

I would just drop back on your fertilizer by 40% and look for improvement in the new growth. Be sure you are feeding balanced nutrients.

Tutorial - A word on Nutrients

The proper use of “salt” based fertilizer to grow Auto Flowering Cannabis. Salts: Natural and man made any chemical compound formed from the reaction of an acid with a base, with all or part of the hydrogen of the acid replaced by a metal or other cation. Learning how to use salt based...

www.autoflower.org

 

[Smokeee]

Ok im going to dump my rez today and try that thanks!

 

[Smokeee]

@Mañ'O'Green i read somewhere that cal mag was the cause for a lot of folks ph fluctuating. And that it isn’t necessarily need this late in bloom should i cease feeding it that as well?

 

[Mañ'O'Green]

@Mañ'O'Green i read somewhere that cal mag was the cause for a lot of folks ph fluctuating. And that it isn’t necessarily need this late in bloom should i cease feeding it that as well?

All nutrients are needed in balance by the plant. Knowing what you have in the pot already is critical to maintaining that balance. study the tutorial the answers are in there.