Digital ph meters and their accuracy and use

I've found using one digital ph meter, that...if you don't keep the bulb wet, the bulb will look foggy.
You suddenly find the meter is crap at realiabilty.
If you look at the tip of the bulb and its foggy looking at the bulb tip, it means the digital ph tester is no loner useful.

We all do the reading and rinse the bulb and place the cap back on. I did that. It still got dried out somehow.

Anyways...I'm rinsing the bulb after each testing and making sure the cap gets put on while the bulb is still wet.

Doing so will prevent the unit from crapping out. It's hard not to want to shake off the distilled water rinse after testing, but you must resist letting the probe bulb dry out. If so, the bulp probe turns foggy in appearance.

In my experience, that says the ph tester is no good from there on.

Preventing the drying out of the sensitive probe bulb is so so critical.

I flush the bulp tip with distilled water after use, and make DAMN sure to place the cap on while there's still water there at the tip.

Others have usefully suggested to keep the probe part of the meter continually wet by simply placing the probe in a small orange juice like glass, and park it there between readings.

This sounds like a good idea, as people rinse the probe afterwards, and place the cap on...but the glass probe dries out eventually.

I've finally found a ph digital meter that works well and is contstant. I'm not letting the bulb probe dry out.
That's the reason for 80% of ppl complaining that their ph meter crapped out!

P.S. Thanks to replies who say they set their PH meter probe in a small of distilled water between readings. Sometimes, just putting the cap back on will still dry out the bulb.

Blue lab. 1 year warranty. The cap has a silicone insert with a cup for the bulb that has a sponge in the bottom to hold the hcl storage solution. You can also find pen style meters that have replaceable/ refillable probes. Bench style lab grade setups can be found used on ebay for pretty cheap money. You can find the modules for $50-100 and new probes for it for $50-80. The setups go for $800+ brand new but lose value quickly on the used market. When my blue lab cashes out i will be going this route.

The worst thing you could store it in is distilled or deionized water. They have storage solutions for them. If you don't want to buy any you can store it in tap water or calibration solution.
https://bitesizebio.com/8750/how-to-care-for-your-ph-meter/

Doesn't go out of calibration, doesn't need calibration solutions, doesn't need storage solution, and is never wrong.

MickFoster said:

Doesn't go out of calibration, doesn't need calibration solutions, doesn't need storage solution, and is never wrong.
View attachment 4053923

Click to expand...

There are better "multi spot" test strips that work better, and have better accuracy.
Can be found rather inexpensively.

Your also right that they never need to be adjusted and are accurate!

M&H makes a very nice and inexpensive meter. I have one that's been neglected and abused. 20 min soak in 7 test solution and a simple reset and she's back in business.
Moves .1 a month and basically holds that for several more.

Still, test strips, never lie!

MickFoster said:

Doesn't go out of calibration, doesn't need calibration solutions, doesn't need storage solution, and is never wrong.
View attachment 4053923

Click to expand...

Tough to determine true colour with nutes mixed in

https://en.wikipedia.org/wiki/Glass_electrode

Between measurements any glass and membrane electrodes should be kept in a solution of its own ion It is necessary to prevent the glass membrane from drying out because the performance is dependent on the existence of a hydrated layer, which forms slowly

Learn to use and care for a glass probe or you will never achieve accuracy across an ionic gradient

Cletus clem said:

Blue lab. 1 year warranty. The cap has a silicone insert with a cup for the bulb that has a sponge in the bottom to hold the hcl storage solution. You can also find pen style meters that have replaceable/ refillable probes. Bench style lab grade setups can be found used on ebay for pretty cheap money. You can find the modules for $50-100 and new probes for it for $50-80. The setups go for $800+ brand new but lose value quickly on the used market. When my blue lab cashes out i will be going this route.

Click to expand...

I just bought a Bluelab pen. Great pen and the design of the cap is extremely well thought out with the cup to keep the probe wet. On other pens you can cut a piece of sponge and put it in the cap and wet it with storage solution.

xtsho said:

I just bought a Bluelab pen. Great pen and the design of the cap is extremely well thought out with the cup to keep the probe wet. On other pens you can cut a piece of sponge and put it in the cap and wet it with storage solution.

Click to expand...

My bluelab stays wet for a few months in that cap if im not using it, which is most of the time now

Kingrow1 said:

My bluelab stays wet for a few months in that cap if im not using it, which is most of the time now

Click to expand...

Do you have a problem getting that cap off? Mine is so tight I almost need a winch to pull it off. Probe stays wet though.

Craigson said:

Tough to determine true colour with nutes mixed in

Click to expand...

I use this chart for a more accurate reading.

I'll check what the cap looks like on my newly arrived "Diliss PH meter". So far it's working well.
$39 for a bottle of storage solution???? Not likely. The pen itself only cost $17.99.
I just don't want the damn bulb to go foggy like my other ph pen did.

Do the caps of these pens do a good job of keeping the bulb wet? I'm hoping they do.
Damn, I feel like opening the pen and watering the bulb down again, just in case it wants to start drying out. Again...why is storing the pen bulb submerged in distilled water a bad idea? Will the water tend to evaporate up into the innards of the pen?

grassy007 said:

I'll check what the cap looks like on my newly arrived "Diliss PH meter". So far it's working well.
$39 for a bottle of storage solution???? Not likely. The pen itself only cost $17.99.
I just don't want the damn bulb to go foggy like my other ph pen did.

Do the caps of these pens do a good job of keeping the bulb wet? I'm hoping they do.
Damn, I feel like opening the pen and watering the bulb down again, just in case it wants to start drying out. Again...why is storing the pen bulb submerged in distilled water a bad idea? Will the water tend to evaporate up into the innards of the pen?

Click to expand...

The bulb is osmotic. It confuses the shit out of it basically. I got a 6 or 8 oz bottle of blue lab storage solution for $12 at my local shop. 3 drops does it. Had the pen and bottle for over a year now. It lasts a long time.

MickFoster said:

I use this chart for a more accurate reading.
View attachment 4054158

Click to expand...

Those drops will not be very helpful when your nute mix looks like this

Thanks. Yes I WILL pay $16 for a proper solution, not $39. So far this pen is actually working well.

It's a $17.99 Diliss ph only meter (damn that name is hard to remember and type out). As long as the bulb does not go foggy, I'm good (I'm thinking).
Thanks again. I know the cap should work ok, but it's nice to KNOW the bulb will not get cloudy using a storage solution. Cloudy bulb = Meter needs to be returned if possible or thrown away if not returnable. That's my experience so far using inexpensive ph digital meters.

I may go back to test strips if this thing craps out for no reason (hehe, I've heard many do). I've already returned another brand. But I would like to believe that an $18 ph only digital meter CAN last longer then 6 months if properly cared for.

P.S. Run it by me again, if you would, why submersing the bulb in distilled water is a no no for storing.

MickFoster said:

Doesn't go out of calibration, doesn't need calibration solutions, doesn't need storage solution, and is never wrong.
View attachment 4053923

Click to expand...

Yup, Nice and reliable but not precise , I still keep a few on standby though just in case

grassy007 said:

Thanks to replies who say they set their PH meter probe in a small of distilled water between readings

Click to expand...

Distilled water is no bueno for ph meters storage solution, Sure way to wreck one quick, If not using a specific storage solution just use regular tap water.....

grassy007 said:

Thanks. Yes I WILL pay $16 for a proper solution, not $39. So far this pen is actually working well.

It's a $17.99 Diliss ph only meter (damn that name is hard to remember and type out). As long as the bulb does not go foggy, I'm good (I'm thinking).
Thanks again. I know the cap should work ok, but it's nice to KNOW the bulb will not get cloudy using a storage solution. Cloudy bulb = Meter needs to be returned if possible or thrown away if not returnable. That's my experience so far using inexpensive ph digital meters.

I may go back to test strips if this thing craps out for no reason (hehe, I've heard many do). I've already returned another brand. But I would like to believe that an $18 ph only digital meter CAN last longer then 6 months if properly cared for.

P.S. Run it by me again, if you would, why submersing the bulb in distilled water is a no no for storing.

Click to expand...

The bulb works through osmosis. If you have a bucket of water, divided into 2 sections with an osmatic membrane with distilled water (0 Ppm) and the other with tap water (500 ppm) through osmosis, both halves will eventually be 250 ppm. In the bulb is a solution of potassium chloride. The bulb itself takes the reading through osmosis. Distilled water and the solution in the bulb do not play nice together. Its like trying to take an accurate measure of volume and your measuring cup has a hole in the bottom.

So...don't use distilled water as the best way to store a PH meter. Distilled water is good for cleansing the bulb between immediate readings, not so good for storage. Noted noted and noted. Tap water is a better storage solution. Or spend $6 on a PH meter storage bottle. Calibrating is a hassle. Keep the bulb in tip top shape and it should only need calibrating every once in awhile.

That's my take on inexpensive PH meter readers. If you're one of the unlucky ones who received an assembly line defective unit from the get go...send it back and hope for the best.

Then...report back.

I don't know if this is true for all pens, but my hanna has a big fat, bold print warning about not using distilled water as a storage solution in the manual.

That may account for half the negative reviews. Letting the bulb fog up or dry out.

Thanks for the info about not storing the unit wet with distilled water.

I bought a $6 probe store solution that I use to store the unit in. You can store it in a test solution too.

If the probe bulb fogs up...game over. At least that's what I've observed, first hand.