Extech PH100 on the way ... now what else do I need?

[awakephd]

I am getting a PH100 meter for my birthday.

What else do I need to have on hand in order to use it? I assume I need 4 & 7 buffer solutions -- anybody got a recommendation?

Also, I see in the manual that I accessed on-line that the electrode has a limited life. How quickly does the electrode have to be replaced?

Thanks in advance!

[Curdtastrophe]

Good questions.
I anxiously awaiting the answers.

[ArnaudForestier]

I get my 4 and 7 buffers from Get Culture.  Very reasonably priced, IMO.   

In my experience, the electrodes last quite awhile.  I went through several PH-100's initially, as the quality control was really rough - I think 6 or better, when I first got them.  But that was years ago and the customer service people never blinked, just shipped out a new one without questions asked.  The one I have now has been completely reliable. 

[Spoons]

Nice purchase awakephd!

You can buy 4 & 7 calibration juice at your local gardening store (specialty store, not the gardening section at Home Depot). It's really cheap. I get 500ml bottles for $5 and lasts about a year.

I also bought an electrode cleaning solution. I used it once when I bought my Exstik PH100 and haven't used it since. I don't feel like I need to use the cleaning solution as my calibrations are almost always on the dot. So for a hobbyist cheesemaker, I'd say the cleaning solution might not be worth it as long as you take good care of it.

[awakephd]

Okay, here are three options from Amazon:

http://www.amazon.com/CL03-0213-1000-Buffer-Solution-4-00-0-02/dp/B00MX3KVG0/ref=sr_1_7?s=industrial&ie=UTF8&qid=1414590436&sr=1-7&keywords=ph+4+buffer

(Price is right, but the shipping is a killer I think I'll pass!)

http://www.amazon.com/Atlas-Scientific-Calibration-Solution-10-0/dp/B0063MWYMQ/ref=sr_1_28?s=lawn-garden&ie=UTF8&qid=1414590530&sr=1-28&keywords=ph+4+buffer

(Includes all three reference points ... but it looks like I really only need 4 & 7)

http://www.amazon.com/General-Hydroponics-4-01-Calibration-Solution/dp/B004HE7W42/ref=sr_1_20?s=lawn-garden&ie=UTF8&qid=1414590493&sr=1-20&keywords=ph+4+buffer

I'm leaning towards this last one, but I'm not sure how much it matters that the solution is 4.01 rather than 4.0 -- ??

[awakephd]

Update -- I bought 4.0 and 7.0 Atlas Scientific solutions, 8 oz each for around $8 each on Amazon.

As best I can tell, this unit does NOT use a special solution for storing the electrode, correct? (It says to keep the sponge in the cap soaked with ph 4 solution.)

When calibrating, should I put the electrode into the bottle of calibration solution, or pour a little of the calibration solution into a small cup? (May be a dumb question ...)

[ArnaudForestier]

I simply keep my meter submerged in a small vial of 4.0 buffer.

[Spoons]

Update -- I bought 4.0 and 7.0 Atlas Scientific solutions, 8 oz each for around $8 each on Amazon.

As best I can tell, this unit does NOT use a special solution for storing the electrode, correct? (It says to keep the sponge in the cap soaked with ph 4 solution.)

When calibrating, should I put the electrode into the bottle of calibration solution, or pour a little of the calibration solution into a small cup? (May be a dumb question ...)

Yeah, just keep the sponge moist with ph 4 solution when storing. I store the meter upright, so the solution doesn't dry out in the sponge, maybe not necessary though. Sometimes I take out the sponge and rinse it and dry it before adding more ph 4, just to make sure the sponge doesn't get nasty.

Also, calibrate in tiny cups. You don't want to spoil your bottle content. Throw away the solution in the tiny cup afterwards.

VERY IMPORTANT: I just remembered this, Don't use distilled water to wipe the electrode.

[awakephd]

Eric, say more about the distilled water -- IIRC, the manual says something about rinsing in tap water (?) -- do you do that, or ??

[Spoons]

I found the reference from an old thread. It's a comment from Linuxboy. You might not know him as he's been away on another project, but he's like the Walter White of home cheesemaking.

https://cheeseforum.org/forum/index.php/topic,6917.30.html


I've been using tap water to rinse off and I wipe it dry with a paper towel. It hasn't damaged anything and the probe is still reliable one year and 20+ cheeses later.

[qdog1955]

Just got my Extech Friday -----with the 4.01 you described--hope that works------bet you have the same problem I have ----when and how to use the darn thing-----it seems I have to unlearn some of the things I have been doing and start experimenting--again.
  WE will be triumphant!!
By the way---I have seen some negative stuff about Extech-----having owned other equipment from them for years----I know they are a solid company, that backs their products----if you have any problems just don't wait to long to contact them.
Qdog 

[awakephd]

Thanks, Eric -- very helpful! Yes, I have seen Linuxboy's posts; as I recall, he was announcing that he would have to step away from the forum for a while just about the time that I started participating.

[ArnaudForestier]

Awake, I'm sure this isn't news to you, so please forgive the intrusion to your thread.  But in case other, less experienced people might find this useful, here's my $.02 on Pav and others. 

Dig through his stuff.  Pav (Linuxboy) has been the single greatest source of help and information for me.  He's unqualifiedly the most knowledgeable person I've met, and that goes way beyond cheesemaking and dairy science.  There are a few others - in no intended order, as they've all been so helpful: 

Alpkäserei, too, has played a pivotal role in my approach to alpine cheesemaking (my singular love, really). It's Alp and Pav who together lit my fire in embracing a traditional approach to making the hard alpines - whey cultures (as opposed to pure, bought culture strains), traditional methods, making one's own rennet, etc.  Really, embracing the traditions codified since at least the time of Caesar, traditions that have stood the test of time in making truly extraordinary alpine cheeses (Alp's love is justifiably all things Swiss, and mine, all things Savoie) almost in defiance of the incessant press of modernity.

Jim Wallace is an expert in all things Alpine as well, and he's got tremendous information to sift through (check out his thoughts here, his recipes and/or classes on New England Cheesemaking.com, or his blog). 

Also, for what it's worth, I've learned tons from Francois (in particular, cave construction, pyrenees tomme making, thoughts on Beaufort, alpine affinage, semi-firm makes and cultures generally), and Sailor as well.  Sailor is a trained microbiologist.

[tally]

I found a post by linuxboy very helpful when my Extech was acting a little wonky. I forgot to bookmark it but as I recall it was around 2011. I found it when I typed in "pH meter" in the search box here on the forum. My readings were all over the place. Turns out my probe needed a good cleaning. I soaked it in contact lens cleaner, then vinegar then washed it in hot soapy water. Problem solved and it's worked perfectly since. Mostly the pH 4 buffer solution works well, but once in a while deposits build up (protein, fat and salts) that need to be cleaned off.

[awakephd]

Thanks, Arnaud and Tally -- somehow I had missed these replies until now!

Qdog, I am indeed a bit unsure how to use the thing, but I am having fun experimenting. For now, I am continuing to follow the recipe as I otherwise would, but trying to check PH along the way to see how it changes.

Which brings up a question: When I check PH with this, I am not entirely sure of the reading I am getting. It starts out immediately with a flashing reading, which typically rises over a few seconds, and then the reading stops flashing. But the reading continues to rise a bit if I continue to hold it in place. Which reading should I be trusting -- presumably the one when it stops flashing?? (This is something the very limited manual does not seem to address!)

And a follow-up question, to which I think I know at least one possible answer: where should I be looking for PH targets? I think, based on others' posts, that one answer is Giancallis Caldwell's book, which I am anxious to get. Maybe that will be a Christmas present ... but are there other places I should be looking?