PH meter calibration question

[dontknownuttin]

I have a PH-107 PH meter brand new. The package also contains two packs of "calibration mix. My question is after calibration how long before you are required to "calibrate" again?. I only have two packs of this calibration powder mix, Does this mean I can only use this device two times before I have to "calibrate" again?

 

[Royal Nugs]

Calibrate your pen. Then find out what the ph is for your tap water. This should stay consistent so you can use your tap water, or any other stable ph liquid to see when it's time to recalibrate. I use my tap water and distilled water. My tap is always 8.3-8.4 and distilled 6.7-6.8. Margin of error is not critical for ph IMO. My pen drifts down after a month or 2.

 

[Gordo41]

Once you mix up the pack of 7. PH solution in a glass jar, you can keep using the same solution, over and over for about 4 months.
you can buy the packs on ebay for a few bucks for 5 or so packs. I think you mix the powder with 250 ml of distilled water.

 

[Clear Haze]

Good ideas. I used the Ph up/down ph test kit to verify my pens reading before putting my trust in the pen.

 

[ZigZag]

Do the same, and recalibrate every week. Mixed one packet in water and kept it in a smaller sized canning jar_air tight. Just like Gordo41. Jar lasted about 4-5 weeks . My tap water is constant at 7.5 so I PH 5 gallons at a time, and that remains stable for at least three days (5 gallons never lasts more than two days for me once they are fully into veg). I tried some organic PH adjustments like lemon juice, vitamin C, etc. and had a hard time getting the same results every time.Became a major hassle. Went back to PH Up and Down solution and everything was nice and easy again. If your untreated water is stable then after a few applications you should be able to measure out a specific amount of adjustment solution and get a pretty constant PH. For me it is about 3/4 teaspoon of PH down solution for 5 gallons.Always get s me to PH 5.75-6.0. Plenty close. Cheers!

 

[dontknownuttin]

I like the idea of first calibrating this device with the powder provided . Then check your house tap water PH ( mine tests at 7.4) just after this initial calibration use your tap water PH number for calibration checks in the future. We do after all have a wide range of PH to work with anyway. 5.5-6.5 I think this tap water calibration method will put the numbers in the ballpark anyway. I will just rinse tip of device in Distilled water between checks.

 

[Gordo41]

My tap water is around 8 but i adjust every time i make up a gal of nutes. I do use vinegar to get it down to where i want,, never had a problem .

 

[dontknownuttin]

Since I only have the use of one arm this tool could be easier then the tube/drop method.

 

[9fingerleafs]

just measure several different consistent-PH liquid, for example, coke and withe vinegar are 2.4 so there you got the low ph. if you also measure bottled water you get a neutral one, and finally to that water add a couple of baking soda to raise ph and measure again. every time u feel your meter is a little of you can recreate the low, neutral and high ph to recalibrate

 

[9fingerleafs]

you just gotta use the same water and amount ob baking soda as well as the brand of the soda or vinegar every time to get consistent results

 

[Tika]

My Blue Lab has a check mark next to ph in the dig read. When it needs to be calibrated there is no check mark.

 

[Karlee]

Okay Gordo you need to write this stuff down for us vinegar? You have the knowledge

 

[Karlee]

I have a Hanna Pen and when it tells me my tub water is 4.90 or a strange number I know it's time and I'll test with the vial once a week. It's so important with the PH

 

[Flockshot]

Thank you for this one.. I am having one of those "why didn't I think of that" moments.

Edit: After thinking about this for a minute why don't they put that kind of information in the books? It would make life easier (and less expensive)

 

[Flockshot]

If you calibrate your meter every time you use it, that will not be too much.

 

[Karlee]

I use mine twice a day and have to calibrate 3 things when I do it... I trust mine more then that.

 

[dontknownuttin]

If I have to calibrate this each time it will not work for me I will stick with the tube and drop stuff and toss this stupid meter thing. Thanks for the advice!

 

[Jibblerjoe]

Do they have to be adjusted everytime?

 

[Jibblerjoe]

Do the ph pen need adjusted everytime?

 

[DirtyNerd]

Hey there,

You can adjust the meter whenever you feel somethings off. I agree with the rest, that a known water PH is one very effective way of making sure the calibration is correct. Always keep your meter in a storage solution. Most pens have a reservoir built into the cap. I have three bottles of calibration solution. One is 4.0, one at 7.0 and 10.0. Keep everything in a warm environment not a cold basement, even your water. Trying to PH anything in a cool environment will give you false readings, unless your pen has a built in temperature adjustment sensor. PH water adjustment should always be done at a temperature between 75 and 80 degrees. Never shake your water mixture as this will give you an unrealistic value. Gently swish the nutrient and water mixture for accuracy.
PH is very crucial for healthy plant development, so even if you calibrate every time it's not too much.

Hope this helps,

The Nerd