A question about my pH

[Haunts]

Thanks to you all for helping me out, i suffer with this same problem every grow. I will try adding some lime to the soil it can't hurt can it? Do i just sprinkle it on to the top of the soil and how much should i use?

This is how my girls (sour crack) are looking at the moment, I'm at day 38 now.

The NPK ratio for the grow nutes is 5-3-3 and the bloom 3-5-4. And i've been following this chart from week 3 but using for example 3ml/1.5L because from what i've read about autos they can be more sensitive to full strength nutes. Also i start from week 3 again from what i've read you shouldn't feed them in the first 2 weeks. I don't use any of the beneficials either.

 

[BR549]

Haunts, run-off testing is notoriously inaccurate IMO, prone to several sources of measurement error...

Just my noob opinion, but I'd say that run-off testing is okay for determining which direction your soil is in (more or less acidic than the water you're adding) but not for accurate numbers. There are just too many assumptions, the chief of which is that the water and soil contribute equally to the run-off. Do they? Maybe, but I doubt it.

 

[Haunts]

I see a couple of people have mentioned the Accurate 8 pH meter, here in the UK the cheapest i can find it is at £125 but i found this http://www.ebay.co.uk/itm/Soil-PH-M...cs-Analyzer-/371182678978?hash=item566c3633c2 which looks exactly the same, could the Accurate 8 just be rebranded version?

 

[The Elvis]

I see a couple of people have mentioned the Accurate 8 pH meter, here in the UK the cheapest i can find it is at £125 but i found this http://www.ebay.co.uk/itm/Soil-PH-M...cs-Analyzer-/371182678978?hash=item566c3633c2 which looks exactly the same, could the Accurate 8 just be rebranded version?

yes add some lime it wont hurt anything just sprinkle it on water it in.. you must have a good PH pen.. Your soils PH is swinging the lime will make it stop..

 

[BR549]

I see a couple of people have mentioned the Accurate 8 pH meter, here in the UK the cheapest i can find it is at £125 but i found this http://www.ebay.co.uk/itm/Soil-PH-M...cs-Analyzer-/371182678978?hash=item566c3633c2 which looks exactly the same, could the Accurate 8 just be rebranded version?

I don't know, but it looks just like it.

 

[Gonzo]

I see a couple of people have mentioned the Accurate 8 pH meter, here in the UK the cheapest i can find it is at £125 but i found this http://www.ebay.co.uk/itm/Soil-PH-M...cs-Analyzer-/371182678978?hash=item566c3633c2 which looks exactly the same, could the Accurate 8 just be rebranded version?

Most probably it comes from the same factory as Accurate 8, in fact Accurate means nothing, the only hit on Google is Amazon page. A reseller in US branded it as Accurate 8 some time ago but it is most probably chinese stuff.

I have just ordered one but I have another PH meter, so I can compare. Otherwise I would not trust this ph meter. Seems that calibration is not possible, what make it quite unreliable.

 

[Haunts]

Can the soils pH be different at the bottom of the pot compared to the top? The reason i ask is because i can't get one those probes for a couple of weeks but a local shop has one of those kits that you take a sample of the soil and measure it against a colour chart, i know its not gonna be accurate but surely it will show if i'm in a low range.

 

[Waira]

...yup, it sure can.... the soil is like a filter (roots too), and towards the bottom, things can become more concentrated than on top,... Something like lime, even if it's powder fine, will not penetrate very deeply if added on top and watered in; successive waterings may help bring it down further, but I don't believe it'll make it the bottom zone,... meantime only part of the soil is being affected by the buffering capacity of the lime,... I've used hydrated lime to better effect, but it's chemically different from Ag' lime, oyster shell, and dolomite, and should be used with great care! It's has right now pH adjusting, because it's CaOH, not CaCO3 + MgCO3, like the other sources,... dolomite is a little different from these as well, bonded in a different configuration, and as such, is the slowest of all to release and react,... Haunts, did you try that run-off testing method I referred to? ...The pH kit will at least get you some idea, yes,...

 

[Heavily Medicated]

I think the whole measuring runoff to determine medium pH is a wild guess at best. On several grows I would measure runoff and take a reading with the A8 also. There was no connection what-so-ever between the two. Almost always the runoff would be way more acidic than the direct A8 reading. Alot of times the runoff pH would be in the 5.7 range, and the A8 would read 6.3. I would not put any worth at all on the runoff method. Just my 2 pennies.

 

[Haunts]

Waira, i need to water them tonight so i'll give it a go, i'm picking up the test strips as well so i'll compare the results. Just to clarify your instructions. Add nutrients to the water as normal and take a measurement - water plants as normal - leave for an hour - place a clean saucer under the pot - then water plant with enough distilled water until i collect enough runoff for 50ml - take measurement of runoff - do equation?