marine monitoring equipment advice

Does anyone have a good marine monitoring program for oceanographic parameters e.g. salinity, temp etc? Are you happy with your equipment? Could you share type and source of your equipment so I can check it out. Thanks so much.

P.s. Thank you Martin, Karl, Peter A. and Armando for the information and thoughts on spearfishing, the information will be useful in the articulation of our policy moving forward. [...]