PH Meter Suggestions


#1

I’ve been negligent and not purchased a quality PH meter. The selection and price range has left me completely confused.
I don’t want to spend a fortune, but want an easy to use, accurate, and durable piece. It will also be used in our mushroom lab.
Any thoughts?


#2

Will you test soils or liquid solutions? For meaningful results you’ll want a meter designed for the media.

Also be aware that the inexpensive 2-3 prong meters sold by garden departments work ok in a retail bagged soil but not so well in outdoor native soils that have modest (or more) clay content. They’re also not designed for liquids.


#3

I will need to test liquids as well as soils/substrates.
Because of our lab work with bio substrates and data collecting, the meter must be capable of the full range and be very accurate.


#4

I’ve never found one that worked worth a damn. Mine always reads 7.0 no matter what, and I know that’s not true. My native (unlimed) soil pH is a hair under 5.


#5

Are you talking about something lab quality like Fisher Scientific? It may hurt your wallet!


#6

Yeah i challenge anyone that has one of those three prong meters to stick it in lemon juice and tell me if you believe what it says!

The HM Digital ph-80 is very cheap easy to use and water resistant, so you cannot leave it in water overnight but it can get submerged and for the price is a great tool, You need to store the probe in clean water or storage solution its entire life. Or you should do the drops or paper method.

Next upgrade is the Bluelab PH pen and then if you want to go all NASA on it the Myron PH pen (made in the usa) but maybe consider the upgrade to a dual PH / EC meter


#7

Use phenolphthalein. I even use it for hydroponics. If it ain’t laboratory grade, it will not last long. Laboratory pH meters are pricey and must be maintained. I have found soil probes to be a complete waste of money. For pH, use phenolphthalein, for correct moisture, use the ‘dirty sanchez’ technique. Stick your index finger deep into the soil, then drag it across your upper lip. If there is enough moisture that your lip feels tacky/wet against your finger, the soil is wetter than optimal. Just my opinion.


#8

Cool. I’ll check out the suggestions. I was on eBay looking at used lab quality units, but I think it’s too risky. They are serious money.


#9

You can get cheap test strips that are about $10 for 100 tests. They have various ranges, 0-14, 3-8 (preferred for soil tests). The 3-9 range test strips seem to work ok in increments of 0.5 pH.
I don’t believe any higher precision is needed as far as soil testing is concerned.
I expect they will be very accurate within that precision range.