pH Probe purchase: which one to buy for RKL?

[swimmingswammi]

pretty straight forward. I know there are some lab quality stuff out there but I figure I will need to learn to work with high maintenance equipment as well. And dont know if I will have access to such experts.

 

[ToXIc]

the only definite i've seen is that you have to use the DA temp probe..
as far as ph and ORP i've seen many ppl using pinpoint's..