The simple answer is no, it’s not possible to go scuba diving without the use of a tank. There are other types of water activities including freediving and snorkeling which you can do without a scuba diving tank.

Freediving is when you go to a depth on a single breath and does not use a scuba diving tank. Many freedivers believe you can get closer to marine life when you’re not exhaling bubbles.

You can also snorkel. Snorkeling is when you swim on the surface with fins and a mask. It is typically done in shallow water and does not require the use of scuba gear.