pH Meters Don't Last Forever!

This thread will explain why copious notes are essential to avoiding failed crops.

My ~ 5 yo Hanna pH /Temp meter (HI 98127) no longer calibrates. I replaced the probe + batteries ~ 1.5 years ago.

I didn't realize that my Hanna probe was giving false readings. I figured this out AFTER adding 4 TBS of pH down and still not lowering the pH. I almost killed my test clones. Thinking about this, I quickly removed 3/4 of the rez nutes replacing them with < 10ppm RO (pH ~9), hoping the rez is now not too acidic.

I did not think about why I was needing more acid than usual (and more and more over the last month), and so did not connect the dots. (I know, what took me so long. Right?)

My 4 test clones took the hit, but better them than my new plants, which are currently in my bubbler. They have not been growing well, either: the nutes were balanced with the old meter. Could be that and/or the <40* temps of late, but I am more suspicious of the nutes pH.

I contacted Hanna tech support. I told him my battery check was showing 9.3. He said that was too low. He then walked me through Calibration, but after doing the steps, WRNG appeared on the screen. He said the probe was bad, and that probes last ~ 1 year. Cost of probe ~ $55. I also needed batteries. Between the 2, it was ~ the same as buying a whole new meter.

There's a place in Atlanta that comes up when you google Hanna. It is $74.99 + free shipping.

Make a note in your calendar to replace in a year will ave you heart ache and crops.

just have the little manual color testers and a digital ph meter and u will b fine if u take the time to make sure everything is correct

Pet: can you get us the name of that supplier in Atlanta and possibly their web address? I've gone through three pens in five years and frankly I'm thinking seriously of going to the litnus paper strips for checking pH. They're not as fast but they work well and with a larger volume reservoir it's still pretty easy. I didn't like the test chemicals and sample vial from general hydro, that was too slow. Neither test method requires calibration and technology is only as good as it lasts accurately, and that's what I have to test my pens against when I'm in doubt. What do you think? HSA

i prefer just to use one of those cheap ph testing kits.because although they wont tell you the exact ph,i do think theyre more reliable.

I have a bottles of calibration solution or whatever it's called. If my meter is put in a bottle with a solution of 0.4 or 0.7 etc, and the meter reads 0.4 or 0.7, that's all there i to it. A lot eaier than noticing that you're suddenly requiring a few more drop etc. I bought a cheap ass digital meter, it's been spot on for almost 3 years.

Save your money, all meters do what you just realized. THESE pH strips are cheap and all ive used for years in my HPAero system.

Just got my new meter. The 2 rezs were 2.9-3.0. No wonder I was having serious issues. Personally, I do not subscribe to litmus paper.

DIYer is probably right in that I was not routinely checking pH in test solution. That may, or may not have made a difference, but most likely would have. Come on guys google the damn thing. Hanna then look for the dealer in Atlanta. It was number one

What are you talking about? "DIYer is probably right in that I was not routinely checking pH in test solution",.. i never said a word of that.

Secondly it's kind of foolish to say "Personally, I do not subscribe to litmus paper". Its been in greenhouses and laboratories for 400+ years for a reason, that reason is it works. Why would anyone trust there grow to a tool you know is going to shit the bed and waste you even more money in a few months. pH strips cost literally one nickel and are right every time, never a need to calibrate a thing.

If it helps anyone in an emergency,I found digital PH meters at home depot the other day.$14.99.Never know..