Megacrop grow in autopots - help?

[BongRipLarry]

I started a Megacrop one part grow. My autopots seemed to be dialed in (haven't had any issues with autopot base running dry, etc), and I've been feeding megacrop at ~550 total ppm (my water typically runs about 60-70ppm from the tap) at pH 6.3-6.4, based on the some of the minimalist approaches to Megacrop growing I've read about. I've got 2 Mephisto autos in a 3x3 I'm running at about 75 degrees and 55% Rh, and the medium is Roots Organic soil. The plant in question is a Forum Stomper.

I mixed up a batch of my standard feed before I had to leave town for a funeral, poured it in the night before I left, then gave the pH a quick check before I took off to make sure everything was good. A week later, I came back to some yellow and rust colored spots on upper leaves, so I dialed the next batch up to ~650 ppm (this was a couple days ago). I'm not seeing improvement - in fact they may look worse. I checked pH in the water in the autopot base and it's around 6.4-6.5.

Any ideas?

 

[namvet25]

Flush with cal/mag than feed bloom nutes at normal dose.

 

[BongRipLarry]

Flush with cal/mag than feed bloom nutes at normal dose.

How do I flush in autopots? And my plan was to use Megacrop continuously, so I didn't have any type of bloom nutes planned - has anyone with mega crop experience encountered anything similar? @Mañ'O'Green ?

 

[JP1]

Happened to me every time with autopots. To flush shut the valve off at the rez and then either take the pots out and put over buckets (recommended), or leave them in and be prepared to shopvac out the trays a lot. Water from the top with just calmag and ph'd water until your ppms are the same coming out as going in. Takes me 6-10 gallons to flush a 5 gallon bag with coco. I don't know if that would waterlog your roots in soil though

 

[Mañ'O'Green]

@BongRipLarry Welcome to AFN Here is the Issue Roots Organic is Soil and you are growing hydroponic. With any sub-irrigation system you will eventually develop a salt line inside the pot where evaporation stops the upward movement of the minerals in the medium. Soil that is pre-amended with Dolomite lime will form this zone much faster than say coco. The accumulation will eventually become toxic. Soil does not flush well and in fact flushing can just make things worse. You should not fertilize soil every day once a week should be plenty.

MC 1part is not very flexible. I recommend 3g MC 1g Epsom salt per gallon for flower. Add a P-K boost at transition and then a little extra (25 PPM) K through harvest.

 

[Jhouse09]

I don't know from personal experience but I'm fairly certain that after you've established your grow bottom feeding and then you top feed as someone mentioned earlier you will likely kill your plants.

 

[Bob's Auto's]

I don't know from personal experience but I'm fairly certain that after you've established your grow bottom feeding and then you top feed as someone mentioned earlier you will likely kill your plants.

If you topfeed in Autopots just put a shutdown valve on the watertank and shut it off for a certain period of time. I top feed my plants rundown worm juice from time to time and when I do always close off the valve until the next day.
That's one thing the Autopot guys forgot to incorporate in their system. A small valve...

 

[Jhouse09]

If you topfeed in Autopots just put a shutdown valve on the watertank and shut it off for a certain period of time. I top feed my plants rundown worm juice from time to time and when I do always close off the valve until the next day.
That's one thing the Autopot guys forgot to incorporate in their system. A small valve...

I was unaware and good information to have I just know all the nutrients and salts build up at the top especially later on in your grow I figured even if you did turn off your water supply and then water from the top it will burn those roots up.

 

[Bob's Auto's]

I was unaware and good information to have I just know all the nutrients and salts build up at the top especially later on in your grow I figured even if you did turn off your water supply and then water from the top it will burn those roots up.

I'm currently on a water only schedule as I'm growing with BioTabs. So there's no root burn risk for me when I do this, but if you want to add beneficials while using MC or another feedline then do so with the least amount of water and close the valve after you have added the top feed.

 

[BongRipLarry]

If you topfeed in Autopots just put a shutdown valve on the watertank and shut it off for a certain period of time. I top feed my plants rundown worm juice from time to time and when I do always close off the valve until the next day.
That's one thing the Autopot guys forgot to incorporate in their system. A small valve...

I'm wondering about trying a flush - I have valve coming out of reservoir, so I can turn off autopots while I flush.

I'm just wondering if the plants would survive a fiush followed by a move back to Megacrop nutes.