EC/Ph of run off - fabric vs plastic pots - variation help?

[NZ_]

Hi,

So I'm flushing my plants.

2 of the plants are in plastic pots and 1 of the plants is in a fabric pot.

I've been measure the EC and Ph run off of all three and I'm finding the fabric pot has varying readings.

Example:

Run off reading taken 1 minute after flood with Ph 6.0 water:
- The plastic pots give a reading of say 400 at 500ppm and 6.3 PH
- The fabric pot gives a reading of roughly 500 at 6.7 PH

Run off reading taken at 3 minutes after flood with Ph 6.0 water:
- Plastic pots are reading 500 at 500ppm and 6.4 ph
- Fabric pot gives a reading of 900ppm and 6.6ph

What is causing this? Why are the plastic pots flushing differently from the fabric pots and why are the readings different further apart?

I am taking the water from the saucers before the saucers auto drain.

[M_C]

Good question. I've only really measured my run off when the run off is in full flow rather than at the start or end.

[NZ_]

If I measure it when its in full flow - it is much lower than if it gets a chance to pool in the bottom of the saucer for a bit. Almost as if its flooded so much that half the water isn't getting a chance to interact.

[Elias]

If I measure it when its in full flow - it is much lower than if it gets a chance to pool in the bottom of the saucer for a bit. Almost as if its flooded so much that half the water isn't getting a chance to interact.

Surly the saucer has dried salts in it giving a higher reading?

I only ever check run off if there’s an issue showing...

[M_C]

Surly the saucer has dried salts in it giving a higher reading?

A very good point! Always make sure whatever you collect the run off into is clean!

[Uv123_4]

Good thought. I thought I was havin same issue. I’m feeding my cindy in coco and the ec was coming out stronger each day. Maybe it is the salts from last time. I’m goin to wash tray before I next water and check again. Was goin to post but saw this post.

[Farmer Geddon]

Measuring runoff is a hiding to nowhere. Even if the runoff wasn't 'contaminated' by the fresh nutes coming in, the information is of no value. I have seen a grow completely wrecked because importance was given to the pH of the runoff. The only important thing about runoff is that there is enough of it. 15% to 25%. More than 25% runoff hurts the wallet, not the plants.

With passive hydro, the ec and pH only has to stay within range for 24 hours. If your plants are all green, then the ec and pH are within range.

[NZ_]

Hmm some good points - thanks team.