What is the name of the tank used in hydrotherapy for immersing body parts or the entire body?

The term that is most commonly used for the tank utilized in hydrotherapy for immersing body parts or the entire body is "Whirlpool." This equipment is specifically designed to create a soothing and therapeutic experience through the combination of warm water and agitation. The whirlpool's jets can provide gentle massage and resistance, which are beneficial for rehabilitation and pain relief.

A hydro tank generally refers to a more generic water container and isn't widely recognized as a specific treatment tool in physical therapy. Similarly, while a therapy pool is used for rehabilitative exercises in a larger setting, it doesn't focus on the individual immersion of body parts like a whirlpool does. A water bath could suggest a simple container of water but lacks the specific therapeutic functions associated with hydrotherapy treatments. Therefore, "Whirlpool" is the most accurate descriptor for the equipment known for its specific role in hydrotherapy.