Am I due a new pH meter?

[tokeycones]

Hey growers, so i've been having some ph issues lately my plants started off very healthy for the first 3 weeks as usual i was phing to 5.8 growing in coco coir with synthetic nutrients. One of my critical kush started showing mag deficiency so i just upped the doseage thinking she was a bit hungrier. after about a week they have all shown deficiencys . If i freshly recalibrate my pen it seems ok but then the next day i test the same tap water and it reads .5-.7 higher than it did the day before. When seeing this i went to recalibrate again and it read 7.4 in the 7.0 cal solution...Ph pen is about 5 months old Bluelab range. They aren't cheap so want to make sure it's the pen before purchasing a new one.tyia

 

[Chris Scorpio]

What I have done and do is use two cheap pens

Now since u have a good pen, get a $15 as a backup to test yer pen

Or

Get a new one

I'll be getting a new one probably today

Looking at Apera, so we shall see

 

[Old Salt]

Your pen is starting to go.

I use a HM Digital pH-200. They run $66.59 USD on Amazon, and you can replace the probe for $25.99. It's more accurate than the Bluelab with the display being ±0.06 pH while Bluelab's offering is ±0.2 pH. I think the HM Digital pH-200 is a much better pen a lower cost.

 

[tokeycones]

What I have done and do is use two cheap pens

Now since u have a good pen, get a $15 as a backup to test yer pen

Or

Get a new one

I'll be getting a new one probably today

Looking at Apera, so we shall see

Ye i bought a cheapo pen just to compare with be here tomorrow so i'm sure ill have a verdict.

 

[Chris Scorpio]

I use two, like I said, just to check each other

They are probably .2 different ish normally, so as long as they are that close I know they are in line

 

[Sctanley007]

May sound stupid but did you replace the batteries? That might be the culprit.

 

[tokeycones]

May sound stupid but did you replace the batteries? That might be the culprit.

No haha. shit worth a shot i guess.

 

[Old Salt]

They are probably .2 different ish normally, so as long as they are that close I know they are in line

I check the calibration before each use to be certain of my reading, and re-calibrate if needed. I did this with the cheap pens as well. The way I use them keeps them alive much longer than most.

Turn on the pen and put it into the calibration solution
Rinse, take my reading, and adjust the pH of my nutrient solution
Rinse the pen, and put it back in the calibration solution
Rinse the pen and close the cap (with its storage solution).

I rinse with water from my RO. The first sensor for my HM Digital pH-200 lasted over three years, while many folks complained they only lasted 6 months to a year.

 

[Sctanley007]

Only reason I thought of it was the thermostat to my home is digital and it was reading temps all over the place. Didn't even know it had batteries...replaced them and perfect. definitely worth a shot

 

[tokeycones]

This is only my 2nd grow so it may be some thing i'm doing however i think it matches the ph being off and i'm following the same method of my first grow which was great . day 45 below day 21 is the younger pic was when they were the healthiest

 

[tokeycones]

Only reason I thought of it was the thermostat to my home is digital and it was reading temps all over the place. Didn't even know it had batteries...replaced them and perfect. definitely worth a shot

temps are correct on mine as my ec pen gives the same temps.

 

[Barney86]

I use the Essentials pH pen. Was only £50 and although I've currently lost it somewhere in the abyss, it was still spot on after a year last time I checked. Check it against bottled water and was always bang on the money.

 

[LiberalThinker]

Hey growers, so i've been having some ph issues lately my plants started off very healthy for the first 3 weeks as usual i was phing to 5.8 growing in coco coir with synthetic nutrients. One of my critical kush started showing mag deficiency so i just upped the doseage thinking she was a bit hungrier. after about a week they have all shown deficiencys . If i freshly recalibrate my pen it seems ok but then the next day i test the same tap water and it reads .5-.7 higher than it did the day before. When seeing this i went to recalibrate again and it read 7.4 in the 7.0 cal solution...Ph pen is about 5 months old Bluelab range. They aren't cheap so want to make sure it's the pen before purchasing a new one.tyia

Are you storing the pen wet in the KCL solution they supply? The bulb must never be allowed to dry out. Vitalink do a narrow spectrum range (0.2 increments) pH chemical test that you could use as a backup that's not expensive.

 

[tokeycones]

Are you storing the pen wet in the KCL solution they supply? The bulb must never be allowed to dry out. Vitalink do a narrow spectrum range (0.2 increments) pH chemical test that you could use as a backup that's not expensive.

No as they solution that came with the pen was extremely minimal. It was fine for me the whole first grow i just made sure to cap it after each use asap however this is a more likely scenario than any above thanks for mentioning it , i have a friend in dire need for a pen so i just bought a new bluelab pen , i'm going to compare if it's bung he can replace the probe. if it's fine win win for both of us.

 

[tokeycones]

Are you storing the pen wet in the KCL solution they supply? The bulb must never be allowed to dry out. Vitalink do a narrow spectrum range (0.2 increments) pH chemical test that you could use as a backup that's not expensive.

The thing that puzzles me that i forgot to mention. i tested it with malt vinegar it took it straight to 2.4 where it should be. what are the chances of wide ph fluctuations in my local tap water?

 

[LiberalThinker]

No as they solution that came with the pen was extremely minimal. It was fine for me the whole first grow i just made sure to cap it after each use asap however this is a more likely scenario than any above thanks for mentioning it , i have a friend in dire need for a pen so i just bought a new bluelab pen , i'm going to compare if it's bung he can replace the probe. if it's fine win win for both of us.

Make sure you get some storage solution for your new one. I think they do a maintenance kit. I just got their EC truncheon... it's fab.

 

[tokeycones]

Make sure you get some storage solution for your new one. I think they do a maintenance kit. I just got their EC truncheon... it's fab.

I bought the maintenance kit to go with this one hopefully both arrive tomorrow i got the combo care kit for ph/ec

 

[LiberalThinker]

The thing that puzzles me that i forgot to mention. i tested it with malt vinegar it took it straight to 2.4 where it should be. what are the chances of wide ph fluctuations in my local tap water?

Definitely. I wouldn't be surprised to see quite a variation in tap water. I certainly wouldn't judge the performance of a meter with it. You need to use known reference solutions. You've got good gear, don't skimp on the gear necessary to keep it in good order. Good technical science gear is expensive and needs to be babied if you want it to last. I think the sensor tip on a pH meter should be good for two years - if looked after - before it needs replacing.

 

[tokeycones]

Definitely. I wouldn't be surprised to see quite a variation in tap water. I certainly wouldn't judge the performance of a meter with it. You need to use known reference solutions. You've got good gear, don't skimp on the gear necessary to keep it in good order.

Ok so the only thing with an exact ph someone told me was 2.4 for vinegar i used it on this and it was correct. any other ways to test my accuracy you can suggest? The fact that i calibrate one day then the next i go to recal and it shows 7.4 in 7.0 solution just made me think it's the pen. 100% i will take care of the next one

 

[Barney86]

The thing that puzzles me that i forgot to mention. i tested it with malt vinegar it took it straight to 2.4 where it should be. what are the chances of wide ph fluctuations in my local tap water?

Check it against bottled water mate. Most big brands have the pH in the bottle.