Bluelab Truncheon is the gold standard for hydroponics. It's a no-brainer and it's waterproof and yes, it will get plenty wet rain or shine! As for price; Bluelab's is pricey, but you get what you pay for!

You can get by very well using pH test paper, available at the drugstore.
Hydro stores cary pH and EC metering devices; pet stores cary goldfish.

davemichigan,

I'm not an expert, but I agree with freemangreens re. the Bluelab Truncheon. I've used one for two years and it works great. I have used a Hanna pH meter (HI 98127) for the same period. It's very slow to stabilize ... it takes over 45 s to get a reading, whereas with the Hanna, its less than 10 seconds.

Waterproof is good

Same here with the bluelab, the best choice.

My pH meter is also Hanna (HI-98128), virtually the same as dennyg's. It's served me well and I wouldn't go back to the liquid/tube/chart type kit.

I bought this pH meter because it was waterproof, I don't trust myself not to drop the thing in my tank someday!