ISFET mini lab PH pen is what I use. Going strong for over 10 yrs now, never a problem. It uses a silicone type tip instead of the cheaper glass tips. Just wipe it clean when finished, it stores dry. Calibrates with 2 drops on the tip.
They have different models. Mine was $200 10yrs ago. After using every brand with the glass tip and tossing them after a yr, I payed the extra$ and glad I did. Never seen the OP mention not affording a $100 pen...i just googled that ph meter because i was interested in the 10 year longevity.
1,131$ lmao i cant afford that haha, the op can hardly afford the 100$ pen i thought