Grow Mediums Runoff pH question

[DCLXVI]

I initially posted this in the wrong thread so....


What's everyone's take on runoff pH? This is regarding a solocup grow so volumes etc are in relation to an 18oz cup.

Should I even worry about it if input ppm/pH is in range? I know ppm can be watched easily and if it starts climbing to back down the feed strength or up the input volume and runoff amount. If the runoff pH is dropping precipitously should I change anything or not worry about it?

I've been running in at about 520ppm for the last couple weeks and varying pH going in from 5.8-6.2 sticking to 5.9/6.0 as much as possible. Runoff ppm is sticking in the mid 400's, crept up to 615 but some extra volume brought it back to near 550 again. Typical irrigation volumes have been 250-300ml and getting an average of 70ml runoff, 20-30%.

However, runoff pH has dropped from 5.5 to 4.3 or lower! I watered in 520ml split between 7am and 3pm sessions. It went in at 520ppm and 6.1pH. Measured runoff before the evening watering at 198ml of runoff reading 424ppm and 4.0pH. I expected higher than usual runoff volume as I am less busy and can water 3x a day.

I was worried the runoff pH is far too low and there could be a salt build up despite the ppm numbers not suggesting it. I did calibrate the pH meter in case that was the culprit.

I just ran a full 1000ml of 400ppm 6.3pH through the cup. I broke it up into 4 250ml waterings.

4x250ml in with runoff at:

1) 112ml out 339ppm 4.6pH (evening watering)
2) 240ml out 365ppm 4.4pH
3)250ml out 385ppm 5.3pH
4)250ml out 392ppm 5.2pH

Should I worry about runoff pH at all or am I chasing a non problem? Plant looks fine except for maybe 4 leaves here and there.

 

[Del boy]

I initially posted this in the wrong thread so....


What's everyone's take on runoff pH? This is regarding a solocup grow so volumes etc are in relation to an 18oz cup.

Should I even worry about it if input ppm/pH is in range? I know ppm can be watched easily and if it starts climbing to back down the feed strength or up the input volume and runoff amount. If the runoff pH is dropping precipitously should I change anything or not worry about it?

I've been running in at about 520ppm for the last couple weeks and varying pH going in from 5.8-6.2 sticking to 5.9/6.0 as much as possible. Runoff ppm is sticking in the mid 400's, crept up to 615 but some extra volume brought it back to near 550 again. Typical irrigation volumes have been 250-300ml and getting an average of 70ml runoff, 20-30%.

However, runoff pH has dropped from 5.5 to 4.3 or lower! I watered in 520ml split between 7am and 3pm sessions. It went in at 520ppm and 6.1pH. Measured runoff before the evening watering at 198ml of runoff reading 424ppm and 4.0pH. I expected higher than usual runoff volume as I am less busy and can water 3x a day.

I was worried the runoff pH is far too low and there could be a salt build up despite the ppm numbers not suggesting it. I did calibrate the pH meter in case that was the culprit.

I just ran a full 1000ml of 400ppm 6.3pH through the cup. I broke it up into 4 250ml waterings.

4x250ml in with runoff at:

1) 112ml out 339ppm 4.6pH (evening watering)
2) 240ml out 365ppm 4.4pH
3)250ml out 385ppm 5.3pH
4)250ml out 392ppm 5.2pH

Should I worry about runoff pH at all or am I chasing a non problem? Plant looks fine except for maybe 4 leaves here and there.

Hello i never check run of as long as get my 30% run off each water i find that to be fine but i am no expert it just works for me

 

[St. Tom]

with me i just concentrate on what I'm feeding her as del said

 

[DCLXVI]

Thank you both for answering. I did google the issue and saw various things across other forums. I trust my friends here so if you guys don't worry or measure it, I will let it ride unless I see an issue crop up on the plant itself. Just a bit of overprecaution as I'm new to coco.

 

[Trichome farmer]

Thank you both for answering. I did google the issue and saw various things across other forums. I trust my friends here so if you guys don't worry or measure it, I will let it ride unless I see an issue crop up on the plant itself. Just a bit of overprecaution as I'm new to coco.

i hate to be the one to have a different view buuuut if my runoff was 4,0 id be doing a flush to get it back to 5.8-6.2 range i did it at the start of this run 1st week of flower ph dropped to 5.4 so did a flush back to 6.0 and it has stayed there until this week where is has started to creep up to 6.4 so il adjust back down toward 5.8

 

[DCLXVI]

Interesting. I appreciate the opposing viewpoint. I think since I've just started with coco, I will keep a close tab on it and record values. If I see issues on the plant I may adjust accordingly. I could also try a side by side and maintain higher pH on one and let the other ride. There doesn't seem to be a consistent answer.

I am confused by the 1000ml flush. It did not really bringing the runoff pH up very much at all. PPM count is low so, where is the acid hiding?

 

[Trichome farmer]

@Mañ'O'Green might have the correct answer your seeking

 

[St. Tom]

i hate to be the one to have a different view buuuut if my runoff was 4,0 id be doing a flush to get it back to 5.8-6.2 range i did it at the start of this run 1st week of flower ph dropped to 5.4 so did a flush back to 6.0 and it has stayed there until this week where is has started to creep up to 6.4 so il adjust back down toward 5.8

I totally agree on a bigger pot but a solo cup is a whole different lady but there are more than 1 way to skin a cat not that I'd ever skin a cat as I'm an animal lover

 

[DCLXVI]

I know he does. I hate bugging him on things I feel like I should be able to figure out. @Mañ'O'Green - Your expertise?

 

[Trichome farmer]

I totally agree on a bigger pot but a solo cup is a whole different lady but there are more than 1 way to skin a cat not that I'd ever skin a cat as I'm an animal lover

i did think about that after i posted solo cups have their own rules