Soil slurry

[TheGoodFarmer]

Anyone want to share there methods for doing a slurry test? I have never done one but I think my pH is low. I am growing in Ocean Forest. Is slurry better then runoff?

[9fingerleafs]

Complex soils like fox farms don’t need to be phed in theory. If you are providing nutrients regularly then runoff is your best way to monitor ph. If you just want to make sure your bag is at the right ph and all the bacteria and mycos are alive then a slurry test will work. Doesn’t really matter how much water you use if you use ro or distilled water. Just make sure you let everything move around and dissolve into the water before testing

[MeEasy]

I take a tsp of soil from three sides (for an average) of my pots into a rocks glass fill about 2/3 with distilled water and stir let it settle a little and test it. You'll want soil from down in your pot (obviously not to the bottom) not off the top I use my hands to keep damage to the roots at a minimum. I don't trust runoff test because I use fabric pots and they hold onto the salt bad and there's no way it's accurate

[MeEasy]

I'm thinkin the ph meter you are using is off the ph should be 7 or slightly lower after it's out for awhile. Moving on I only dig down a couple inches like the length of the teaspoon not the handle it might be different from the roots but I'm not going to hurt the plant trying to make it feel better lol

[9fingerleafs]

Trying to measure pH of distilled water will mess up your meter. No ppms means no ions means the ph is extremely volatile and will drift in contact with oxygen or CO2

[Rwise]

Like said, distilled water will damage your probe, and it is acidic in nature not neutral, and cant be tested without adding stuff to it.

[Rwise]

Take samples from at least 3 places, drop them in a food processor, pulse a few times, let settle and test. My soil gives 8.4 from the compost doing this.

[MeEasy]

I can't find anything that says that distilled water will hurt your meter will you guy share where you got that. I found out why I got a reading under 7 all the time though

[9fingerleafs]

https://bacto.com.au/ph-electrode-care-and-maintenance/

[MeEasy]

This is from the site you just gave me. I does say not to store the meter in distilled water but doesn't say not to use it in the d water

rinse electrodes with distilled water before and after measuring a sample

[TheGoodFarmer]

Yeah you guys are not the first to tell me that I heard that from a another grower I know. I told him I rinse my meter in distilled cause I figured that would clean the prob. I started using my well water same I use for watering and my meter began So you guys are basically saying that a pH meter cannot accurately read pure water? If that’s the case it makes sense why it reads high (7.5-8.0). I was always confused about that cause I have tested several store bought brands of distilled and the all have a pH similar to my well and my wells PPM is 170-200ppm depending on rain fall.

[MeEasy]

Distilled water doesn't hurt your meter unless you store it in it. The instructions that came with my meter said to clean the meter in distilled water and then put a few drops of storage solutions on it. Read the site 9finger just provided it says to rinse the meter with d water

Edit = that's why I asked for where it said it not to be a smart ass I honestly wanted to know if I found why I always had problems with my ph. That I had flocked up my meter with d water

[9fingerleafs]

You gotta really get into the science of how the meter works, it holds an ion solution inside a special permeable glass, when contact with such low conductivity it pulls ions from the glass into the water. You wont fuck it up in a single day, just dont be trying to read distilled water pH, add a few drops of something and then take a measurement, tap water, pH down, even a pinch of salt.

[Rwise]

I have a Blue Labs, the instructions say not to use it in distilled or DI water, wash it with tap water and store it in KCI fluid. In an emergency it can be stored in tap water for a short time while the new KCI fluid comes in. Your meter may well vary.

[MeEasy]

Wow never thought trying to help a guy do a damn slurry test could turn into this BS . I never knew that d water would fuck up my meter and when you said it it concerned me so I tried to find what you were saying and couldn't so I asked you for help so I could figure out if this was the answer to my questions on ph because I changed to growing in living soil to get away from salts because everytime I would have an issue it came down to ph and now you guys might have the answer. My meter got damaged by me doing what the instructions said to do and that was use distilled water to clean the meter between every test and when calibrating and the link 9finger posted said the same damn thing mine said.

I was trying to find an answer I thought you had and some damn how it seems I pissed you guys off

[9fingerleafs]

It's all good i dont think anybody is pissed off, its just that ph meters are so delicate that literaly just looking at it the
wrong way decalibrates it. I switched to ph paper strips and never looked back, the meter brands are happy to get you to buy a new one every two years because they just won't last.

[TheGoodFarmer]

yeah i use to do it to and it was to a Milwaukee pH 600 (cheap lol) and I swear the instructions said to just like in your case. The guy who owns the hydro shop that I get most of my supplies from said if you use distilled water to clean it you should then take it to another clean water such as tap or whatever you using to water, but he recommended just keeping all pH meter out of distilled to begin with. I always had the instinct to that using distilled was a good way to keep cal mg deposits of the meter but he very recently told me to stop and it was for the same reason 9fingers stated, it will pull the salt (ions) out of the meter. But he also told me that storing a meter for like a day in calibration solution will completely fix it.

He has had customers come in with meters that they claimed were broken he takes them home changes the batteries and stores the meters in reference solution for like a week then uses them himself for years or gives them out to other grower friends lol. The point being if your meter is giving you trouble after having it in distilled give that a try (like a day should do it). I let my first meter completely dry out for 6 months after getting my HM and used that method completely brought it back to life and it now reads pH like the day I got it and that was $20 piece of shit I got to get started lol and I feel for yeah I still struggle with pH management and have been growing for 3 years.

[9fingerleafs]

Thats some good info. Thanks

[Rwise]

BTW when you mix the slurry in D water it is no longer D water, and do what your meters instructions tell you to do.

[Bowhunterwoody]

Not quite sure if this is going to help or hurt but I worked in an environmental lab for over 30 years and used ph meters several times a day for years with some costing over a grand. We always rinsed with DI. Stored in ph 7 ref when not in use. Had to refill the probes every once in a while with KCl due to evaporation. These were certified by the state and feds every year. Never had any problems with DI. Absolutely had to use it. Then a quick wipe with a Kimwipe and back in the reference soln.

[Bowhunterwoody]

9fingerleafs your absolutely right. At least not on purpose. Measured lots of unknowns but most def weren't DI.

[TheGoodFarmer]

Bowhunterwoody I may self have only ever owned two pH meters but from what I understand from looking at multiple brands they all seem to use the same prob type at the price range most home growers go with, I have never looked at a meter that was over a grand do they use the same prob type as cheaper ones (like $50-$200 rang)?
9fingerleafs same guy told me either KCL or calibration and none of this is brand-specific like I use general hydro calibration 7.0 and sometimes I use Blue Lab solutions, depends on what my supplier (hyro shop) has when I visit. Not saying he knows everything but he does sell the products. and yeah my first $20 meter came with no solution you had to buy separate it also didn't have Automatic temp compensation either so I had to really watch my temp to even be able to trust it.

[Bowhunterwoody]

TheGoodFarmer yea it has more to do to with # if significant digits. Some are accurate out to three places with temp and pressure compensation. Commercial type. Not what most growers use or need. Like 9fingerleafs says you def don't want to store in DI. Rinsing is ok but we always stored in ph 7 buffer. Of course these meters we're never really stored long term.
Calibrated daily and used several times daily. As to probes, most were glass and membrane types cleaned often in dilute acid and soaked and filled with KCL