When I was in the Army in the Canal zone in 1962-63 we were using scuba at that time. My tanks were made from two WW II surplus aircraft oxygen bottles tied together. We did recreational diving and spearfishing on many weekends in different areas of the Bay of Panama on the Pacific side.
Tobago Island was 10 miles or so out in the bay, and there were numerous other small islands and rocks in the area to dive around. Primarily, we only used snorkels, and in certain deeper areas we would use tanks. In an area that was known to have giant groupers, I mean the really big ones the 500 to 900 pound Guys. We did see those, two or three of them going around the bottom about 90 feet down. Their tails were so powerful that they cavitated the water when they moved.
We also dove in the Pearl Island chain, which is farther out in the bay, as well as the barrier reefs on the Atlantic side, including a special diving trip to the San Blas Islands. The sea life there was a totally different environment of tens of thousands of tiny, bright colored tropical fish along with barracuda swimming in water so clear that you had a falling sensation when you entered the water. This is in contrast to the gamefish prevalent on the Pacific side, with a huge variety of life from Moray Eeels, Lobsters, Oysters everywhere, Stingrays, huge Manta Rays, many varieties of Sharks, Hammerheads and other large sharks, etc. wonderful time for a young guy. I have never been anywhere else in the world. That had the quality of skin and scuba diving that you could do in Panama, particularly when you considered you could move from the Pacific to the Atlantic on the same day.