Hydrotherapy tubs use warm water jets, bubbles, and variable temperatures for therapeutic muscle relaxation, pain relief, and circulation enhancement in arthritis, fibromyalgia, sciatica, and sports recovery settings. Whirlpool tubs (single/dual seats, rectangular/butterfly shapes) deliver targeted hydro-massage via air/water jets reducing joint pressure 90% through buoyancy; contrast tubs alternate hot/cold immersion for inflammation control; walk-in home models suit elderly with low-step entry, heated seats. Sessions (15-30 min, 98-104°F) boost endorphins, improve sleep, strengthen immunity via lymph flow, and accelerate rehab used in physio centers, spas, hospitals. Stainless steel tanks (300-2000L) ensure hygiene; avoid open wounds, pregnancy, heart conditions.