MY GUIDE for PH UP PH DOWN

What type of tester meter should I get ? One that mite just work, cause i’em tired of wasting my money on tester’s that won’t work for sh–.
I’em sure their out there some where but I just don’t know which one I can depend on.
Like you said Latewood ( can’t leave ph to chance ) I have over 40 plants in 3 gal buckets and each one can’t read the same ph no way and I keep it clean

Thanks for your help on this ( Both of you )

Will