The link posted by scardinale in https://www.ghielectronics.com/community/forum/topic?id=15219&page=1#msg152822 (2nd post) might be interesting.
Not only the epoxy, but also the sensor provided there.
thanks for the link, those are the perfect sensors for what I had in mind.
No all I have to do is save some money for all those goodies and I can start designing 
@ reuben
I have written NETMF Classes for a few of these sensors (pH, ORP and Conductivity) and am currently using them in Hydroponic monitoring system and a Pool monitoring system. Let me know if you would like me to share the code.
thanks, I’d love to see that code. Always a good way to learn.