The container trapped hydrogen and floated, with a crude spring valve to maintain buoyancy to keep it at a constant depth.

Many fish maintain buoyancy with swim bladders.

For example, larger floats may be used with liquids with specific gravities as low as 0.5 while still maintaining buoyancy.

Successful growth and division for algae relies on a balance between maintaining buoyancy in the euphotic zone (which contains ideal light and nutritional conditions) and avoidance of grazing predators.