I almost wonder that you would be better off to go ahead and get scuba gear and get certified lol.. Also you would not want to SNUBA alone, if the winds changed suddenly it could cause the exhaust from your compressor to go into the intake, and you wont realize your breathing in CO2 not O2, wont know anything is wrong and just breath more and more of it in. Until your 10 feet down and gasping for air.

Get out and fish.