A spiral mixing chamber for dissolving a gas into a liquid, features a new and unique combination of a cap and a mixing plate. The cap may include a gas injector configured to receive gas. The mixing plate may include: a liquid inlet configured to receive liquid, a mixture outlet configured to provide a mixture of the gas and liquid from the spiral mixing chamber, and a flow path configured as a spiral geometry having a spiral that winds in a continuous and gradual curve around a central point from the liquid inlet to the mixture outlet, the flow path having flow path obstructions configured to cause disturbances in the flow which generates turbulent vortices that work to break apart bubbles in the mixture flowing through the spiral mixing chamber or device.