Deficiency from salt build up?

getogrow

Well-Known Member
different spots in the same container will read different readings. also if you cant change the ph then why even test it ? unless your using unknown dirt.
 

Renfro

Well-Known Member
i know but they are not accurate. they will only "help" to tell you if its WAY low or WAY HIGH.
No they are accurate. These arent the garbage ones. My Apera has 2 points of accuracy.

But hey, if it makes you feel better I will yield to your superior experience and intellect.
 

getogrow

Well-Known Member
not trying to be a dick but you have to understand soil and the soil food web to understand. they do not make an accurate meter for pots. it has to be sent to a lab. you also cant change the ph in a container so there is no need in even testing or thinking about it.
 

Renfro

Well-Known Member
He's technically running a soiless mix. Peat based. It's not organic. The best way to see what the roots are experiencing is to test the soil after a feeding. Like lets say I tested my nutes at 6.5 and fed but the "soil" after the feed tests at 5.4 then I need to adjust my feed pH up to move the whole situation up to 6.5 ish.

At least thats what works for me. I have seen the peat based mixes get a really low pH like in the 4's, leaves get that stripey burn pattern, and a flush and a few feedings at a higher pH will push it back up.
 

getogrow

Well-Known Member
"Soil testing can be done with 3 different types of soil pH testers; electronic meters, indicator test strips and chemical colored dyes. In each case you take some of your soil and mix it with water or a buffer solution provided by the pH tester. The water is then tested."
this is just a quick thing i found. you have to take soil out of the pot and mix it with a solution to test ph. there is no other way.
 

getogrow

Well-Known Member
He's technically running a soiless mix. Peat based. It's not organic. The best way to see what the roots are experiencing is to test the soil after a feeding. Like lets say I tested my nutes at 6.5 and fed but the "soil" after the feed tests at 5.4 then I need to adjust my feed pH up to move the whole situation up to 6.5 ish.

At least thats what works for me. I have seen the peat based mixes get a really low pH like in the 4's, leaves get that stripey burn pattern, and a flush and a few feedings at a higher pH will push it back up.
Yes peat is fully organic but some peat does have a REALLY LOW ph .....not useable, your correct. If you buy a potting mix from any store , its going to have lime in it to buffer the ph. If your reusing old peat, then yes it will need amended to keep a stable ph. If your using fresh mix then you just leave it alone. ph'ing the food only raises the ph for a few min till its sat in that soil , then the ph buffers to whatever the pot is. You cannot change it by adding up or down.
 

getogrow

Well-Known Member
im not saying that your not close with that nice meter but to get more accurate then pull out a pile of soil and mix it with a cup of water/ ph solution and then test that after 30 min. it wont be perfect but it will be much more accurate.
 

kingzt

Well-Known Member
The stripey pattern on the leaf is from the pH being way off. Thats the only time I have had that happen. Your soil pH should be checked. I also grow in a peat based mix and the pH can get way off over time.
Thanks for the input renfro. When originally flushed i was getting run off at 6.2-6.3 and since then the ph of the runoff has increased to 6.9. I know promix has lime added in it but if the medium is constantly saturated will that raise the ph? I'm not why this hasn't happened to me before though, I water every day in flower and the ph hasn't crept like this before. Things are back on track nevertheless. I think the stress at the root level then being flushed stressed her out a bit.
 

hawse

Well-Known Member
im not saying that your not close with that nice meter but to get more accurate then pull out a pile of soil and mix it with a cup of water/ ph solution and then test that after 30 min. it wont be perfect but it will be much more accurate.
Not unlike what I do - the NTFG slurry method... Grab some dry soil from the top and sides of the pot, mix it with equal amount 7.0 water and see what you got... Not that different than testing runnoff, but according to the NFTG guys grabbing a slurry gives a better idea of what's going on at the roots.
 

getogrow

Well-Known Member
Not unlike what I do - the NTFG slurry method... Grab some dry soil from the top and sides of the pot, mix it with equal amount 7.0 water and see what you got... Not that different than testing runnoff, but according to the NFTG guys grabbing a slurry gives a better idea of what's going on at the roots.
Yes , its way different from testing runoff only. some runoff , runs around the dirt instead of through it.
It doesnt mattter because you cannot change it with PH'ed nutes.
 
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