Check Water Chemicals Despite having Recurrent water adjustments and a sophisticated filtering process, it is important to trace the chemical amounts of your cold plunge tub. The pH amount establishes how acidic or simple the water is. The proposed pH array for a cold plunge tub is 7.2 to seven.8. https://www.bbb.org/us/ca/santa-ana/profile/health-and-wellness/renu-therapy-1126-1000086335