# Cheap Ph Meter?



## itmechanic (9/1/11)

Ive been using pH strips for measuring my pH and want to upgrade to a proper pH meter.

Ive found this cheap one on ebay pH Meter 

Would this be ok, or do i need to spend more to get something better?

Cheers,
Paul


----------



## felten (9/1/11)

IMO what you want from a cheap pH meter is one with a replaceable probe, the probes have a limited life which can be extended through proper care and maintenance, but they will eventually become less accurate over a pretty short time.

I've been searching ebay for cheap pH meters as well and settled on either the HI 98103 ($30 avg) or 98128 ($80). OFC the more you pay the more features you get, and maybe more accuracy ie. 0.2 and 0.05 respectively in the previous models.


----------



## tavas (9/1/11)

It does not look like it has temperature compensation, so you will need to ensure you calibrate at the desired working temperature of your solution. Also, you will need more buffer solutions as you only have enough for 1 calibration. 

It is a single point calibration, so I would assume you will need more pH 4 buffer if you are measuring the pH of your mash. This will be available at chemical suppliers (Rowe Scientific, pool shops etc). 

For $4 it won't be very accurate nor will it last a long time. These are more suited to general use for your pool etc. 

It just depends on what you want from it. For $4 I would expect it will last as long or maybe longer than a set of pH strips. Then when it dies, throw away and get a new one. You get what you pay for. If you want something accurate and will last, this won't be it.

However for that price I say buy one and try it. Its $4 + $8 postage. That's less than a 6 pack of beer. Just don't expect it to last long enough to pass on to the kids.

Hanna Instruments have a pH checker which may be more suited to repeated use. Check out the HI 98103 model. I found it at around $US30-40 online at a few sites. Or Hanna may have something better for what you want.

edit: Grammar


----------



## Bizier (9/1/11)

I am on my second one of these, breaking the bulb in the first. I am not unhappy with them, esp at price. Beats strips in my opinion. I think I got it even cheaper, as identical items are sold by various sellers. Go for the cheapest.

I just calibrate it to pH 7 before use, and often check it against the pH 4 and pH 10. Provided it is on, which it it always is, it lets me know at least a good ballpark figure for where my mash is at.


----------



## Yob (19/4/12)

thoughts on THIS PH meter?

:icon_cheers:


----------



## Lord Raja Goomba I (19/4/12)

What about this?


----------



## gap (19/4/12)

iamozziyob said:


> thoughts on THIS PH meter?
> 
> :icon_cheers:



From the website

*Operating Temperature : 0 ~ 50 C (32 ~ 122 F) *

Regards

Graeme


----------



## QldKev (19/4/12)

something to think about,

I've got one of those cheap yellow ebay pH meters, and also strips.

The meter takes a while to give a final reading. So I find I need to draw a cup of wort of and leave it to sit for a while.

I prefer using the strips. Takes 2 secs to check, and doesn't matter if you treat it rough. I never pull out the meter anymore.

QldKev


----------



## Ross (19/4/12)

iamozziyob said:


> thoughts on THIS PH meter?
> 
> :icon_cheers:




Accuracy : 0.1 pH 

Measures 5.2 - the range could be anywhere from 5.1 to 5.3. Not accurate enough. Excellent value ph meters available from sponsors of this site  

Cheers Ross


----------



## MastersBrewery (19/4/12)

Lord Raja Goomba I said:


> What about this?



Ross little confused says 0-50c working range but ATC is 0-100c though am impressed with acuracy


----------



## Fourstar (19/4/12)

Ross said:


> Accuracy : 0.1 pH
> 
> Measures 5.2 - the range could be anywhere from 5.1 to 5.3. Not accurate enough. Excellent value ph meters available from sponsors of this site
> Cheers Ross




For someone that consistently hits a mash pH of 5.3, the 0.1 resolution accuracy is MORE than enough for me to keep my mind at peace (not that I use this exact pH meter) for the odd reading I take based on grist used.

In fact, hitting a 5.3-5.5 reading (potentially 5.2-5.6, heck even up to 5.8 could typically be 'ok' dependant on the grist) with these meters would be considered perfectly fine for majority of peoples mashes. The question that really needs to be asked is the purpose of using this pH meter? Curiosity, or wanting to hit the expected pH reading on the head every single time?

If the latter is the case, I'd be going for the more expensive option hands down. Reliability and accuracy I would take if I was using this during every single mash. 
For curiosity or the odd reading here and there? Stick with this, a stick/pen style or a range of papers so you can read your pH for mash purposes and fermentation where required. (Good for sours and fault troubleshooting etc.)


----------



## Online Brewing Supplies (19/4/12)

I think what another brewer was saying is that his are more accurate than the one mentioned.
Even with a error of .10 I would consider this accurate enough for home brewing if you can hit the 5.2-5.4 pH range considering most brewers are not even doing pH readings. Some thing is better than nothing.
I wouldnt turn brewers off buying a budget meter and by that I mean dont buy a $20.00 thing off ebay and expect it to work, you can get meters for less than $100 that are good and have warranty.
A good meter is a good investment.
Nev


----------



## manticle (19/4/12)

Fourstar said:


> In fact, hitting a 5.3-5.5 reading (potentially 5.2-5.6, heck even up to 5.8 could typically be 'ok' dependant on the grist) with these meters would be considered perfectly fine for majority of peoples mashes.





5.8 at mash temps would be closer to 6.1.

I agree with the rest though.


----------



## Ross (19/4/12)

MastersBrewery said:


> Ross little confused says 0-50c working range but ATC is 0-100c though am impressed with acuracy



Hi, thanks for pointing that out. I've checked with the manufacturer & the meter can work 0 - 100 but the probe is only rated 0 -50c. A far more expensive probe can be bought if you want to go higher (I'll check out its cost).
I've changed the site to read 0 - 50c to avoid any confusion.

cheers Ross


----------



## MastersBrewery (19/4/12)

Ross no prob, one powerball and we'll have a good talk :beerbang:


----------



## hoppy2B (19/4/12)

And here was I thinking it perfectly acceptable to use a cheap Bunnings soil ph metre at $10.


----------



## Fourstar (19/4/12)

manticle said:


> 5.8 at mash temps would be closer to 6.1.
> 
> I agree with the rest though.




What are you getting at? I'd be reading the temps at room temperature (or as close enough to 30deg~)


----------



## manticle (19/4/12)

Just pointing out there is a significant difference between reading mash at mash temp and reading it at room temp that needs to be considered with any values mentioned, but particularly those that are at the extreme edges of the range.

I use strips which means I measure at mash temp.

Doesn't matter what temp you read it at as long as you know the appropriate range at each temp (or how to correct).


----------



## Fourstar (19/4/12)

manticle said:


> Doesn't matter what temp you read it at as long as you know the appropriate range at each temp (or how to correct).



Understood, clarification for those playing at home. 5.8 is acceptable at room temperature for _some_ worts. 

For those that have NFI what their mash pH should be and at what temperature (room or mash). See below


_A number of enzymes are active in the mash and many of them have different pH optima which makes it sometimes confusing to choose the proper mash pH. To reduce that confusion, here are some simple guidelines that can be followed when determining which mash pH should be targeted or deciding if the current mash pH needs adjustment:

Mash pH numbers are given for room temperature (20-25 C/ 70-80 F) mash samples
Any mash pH between 5.3 and 5.8 should be sufficient for most mashes
A mash pH between 5.2 and 5.5 is well suited for infusion mashes with enzymatic strong malts
A mash pH above 5.4 should be used for decoction mashes and/or enzymatic weak mashes (i.e. large amounts of Munich malt or adjuncts) _

http://braukaiser.com/wiki/index.php?title...wing#conclusion

I hope this helps.


----------



## pk.sax (19/4/12)

I have a bunnings soil meter that I use, uncalibrated of course, to get a general idea that things are OKish. use strips to get a better reading but surprisingly, the bunnings meter ain't really off.


----------



## manticle (19/4/12)

What's 'ain't really in pH values?


----------



## pk.sax (19/4/12)

I think it was ~0.5 or thereabouts last time with the ph strip to compare. Good enough to tell its not horribly wrong. Also, I put a bit of tape on the base of the probe and hang it into a bulldog clip on the lip of the keggle tun. Lid on, walk away. Come back later and see if it's moved much either way, esp after a stir. Helps.

Tbh, won't be needing it when the rig is put back together after I get I welded up as I'll be recirculating so it should stay constant after a bit.


----------



## manticle (19/4/12)

So 5.5 could be 6 or 5.0? 5.2 could really be 4.7? 5.6 could really be 6.1?

Not horribly wrong but the logarithmic scale of pH means not horribly wrong could still be wrong enough. As far as pH goes, 0.5 points is till a fair whack.


----------



## hoppy2B (19/4/12)

manticle said:


> So 5.5 could be 6 or 5.0? 5.2 could really be 4.7? 5.6 could really be 6.1?
> 
> Not horribly wrong but the logarithmic scale of pH means not horribly wrong could still be wrong enough. As far as pH goes, 0.5 points is till a fair whack.



Its probably a case of the metre calibration being off as the temp goes up. I noticed as I heated the mash the reading on my Bunnings metre started dropping a fair bit. I'm planning to calibrate my metre by testing a lemon juice or vinegar solution at different temps and checking the readings with strips.


----------



## manticle (19/4/12)

Temp changes pH so you need to either cool to room temp (~20 degC) or correct to room temp or know how mash temp values correlate to room temp readings.

Mash temp (~60-70) will read approx. 0.3 units lower than room temp, room temp being ~20-25.


----------



## 1974Alby (18/12/12)

manticle said:


> Mash temp (~60-70) will read approx. 0.3 units lower than room temp, room temp being ~20-25.



does that mean that if you are aiming for a 5.2 mash, you would expect a reading of 5.5 at room temp? May sound like a dumb question, but just want to understand your correctly.


----------

