A Meter Challenge

Alright you growing gurus, list the top three meters to buy for hydro testing.

Ready, set, go!!!

(Pictures are a plus, links are saviors)

I've seen those and they do look great!!! I'm just not sure if that is an overkill for my 4 little plants.

Anyone else have any ideas, maybe one that is more expensive and one that is less expensive?

Was looking for this review thanks.

Hanna 3 in one waterproof pen.