PH meter question

Ok so i have a Mettler Toledo SevenGo SG2 Ph meter. It has 4 buffer groups what would the perferred buffer group be?

1. 7.00 4.00 10.01 1.68 (at25*C)
2. 7.00 4.01 9.21 2.00 11.00 (at25*C)
3. 7.00 4.00 9.00 2.00 12.00 (at20*C)
4. 6.86 4.01 9.18 1.68 (at25*C)

Keep in mind that i use this meter for soil and hydro. I am currently using option 2 if anyone with knowledge on this could lend some expertise it would be greatly appreciated.

I have no idea never seen those things before??? I stick my meter in the water and it says the ph is 1-14 like 5.551

What buffer group do you use to calibrate?

Yeah I got a soil meter and when I put it into the soil before it was at 7 and then I put it in watery mud and it still stayed at 7 so I dont know what the fucks goin on granted I did sit on it and bend it a little but its back in shape haah

Man that's all fucking chinese. Just go buy the ph strips. It comes on a roll like stamps did, you dip in water, it changes color, and you check it to the chart on the back. Its just litmus paper. About $7.00 for enough for a year.

If you wanna calbrate you use the solution your manufacture has or reccomends.I have never seen those groups.I have 2 solutions for calibrating ph 4.0 and ph 7.0

Well this is a very high end ph meter and i dont think i will go back to litmus paper or a cheap soil ph test. I dont have any problems with it and works great. I am looking for advise on the 3 - point calibration process. I would like to figure out which option is the most accurate for my uses. thanxs in advance

FilthyFletch said:

If you wanna calbrate you use the solution your manufacture has or reccomends.I have never seen those groups.I have 2 solutions for calibrating ph 4.0 and ph 7.0

Click to expand...

yeah that ^^^^^^^^^...... thats all ive seen.

Yes i understand most people own a ph meter with only 1 or 2 point calibration. I am trying to get advise for us that own a 3 point. I know there is a chemist on rollitup somewhere who will have a good suggestion for me.

Why would you really need that much accuracy in your ph... ??

Seems kind of overkill... =]

Knowing nothing about what those numbers repersent in real life testing i would go with setting 3 as it seems the most generic and you are still going to get a good 2 point accuracy witch is more then enough... =P

Well i have come to realize how important Ph is and so I would like to keep it as accurate as possible. I was just hoping to being using my money to the best of its ability, and hoping it would do the same for me in yeild.

Sorry cant help you I know Blue labs as one of the best but even they dont require that kind of calibration setup.Sounds like yours is more for a lab where .0001 can make a hug difference which isnt so true inplants. Plants are fine with a flux of .2 to .5 flux

Thanks fletch that is exactly what i wanted to know. So i would be best in using option 1 as those are the most common sold buffers so they are the cheapest and easiest to find.I was using 2 because my water or for that matter any test never reaches above 9.21 on the high end. But it is also much easier for me to get buffer solution in the 10.00 - 10.01 range. I guess i asked the question wrong,

Wish I could help but all of those groups are foreign to me I have never seen any calibration solution that carry those numbers. All calbration solutions I have seen either say 4 or 7 on them no decimals as the meter should be able to adjust off the neutral 7 and the low end 4 solution.And you also have celicus on there which throws me even more as I have never seen a temp measurement related to a ph valibration tool and I cant even read celcius only F sorry

Well you were correct earlier when you said that this meter was for labs. That is exactly what it is fo.r but with the use of it i have come to learn that even subtle differences make a change in my plants. So I just got curious,if i was using it to its best. One of those glorious thoughts when i was stoned mind got to wondering.....................

sounds good always is interesting when people find new tweaks for growing

celcius also fucks me up but my meter has atc(automatic temperature control) it also has mtc. 25*c = 77*F those numers are the best temps for your buffer solutions to be at so they will be most accurate.Some solutions are different. as for Celius to Farenheit there are several websites that will do the math for you

my bad atc = automatic temperature compensation i am way to high