[s0rce]

I'm not Ben but having worked in a lot of labs my answer is pH meters, they routinely are annoying, fragile and finicky but there really isn't a better way when you can't just use paper test strips.

[bkraz]

I agree! I've had the best luck with this one, which is far better than the average pH pen from Amazon. https://www.amazon.com/Waterproof-Accuracy-Suitable-Testing-...

[ireflect]

What do you think of the Atlas Scientific pH probes?

[bkraz]

Haven't used them. Looks good. Costs a lot more than the Amazon one, so could be different class with different expectations.