Hey i am looking to buy a PH tester and Oxygen tester for fishing and montering the water in lakes but im have a hard to find specific units made to do just this at a good price. I need a PH tester that i can moniter the PH at the surface all the way down to 15 or 20 feet. And I also need to find an oxygen tester too. I have looked online at bass pro for them but didnt see anything. If any one know any good units please post them. Thanks