Choose the tub from usable volume, insulation, ports, loaded weight and environment. Then size the chiller and pump around that actual vessel.
The main tub types
Specs that matter more than marketing
Record usable gallons, wall/lid insulation, port size/thread, empty and filled weight, interior dimensions, drain design and environmental durability. The calculator can estimate geometry when dimensions are missing, but measured volume and known insulation give higher confidence.
Tub choice changes chiller size
Two 100-gallon tubs can have dramatically different heat gain. A foam-insulated tub with a fitted lid can need much less holding power than an exposed stock tank. Use the tub as the first input to the chiller calculation.
How to use tub “best-of” pages
ChillSizer does not rank a tub because it pays a higher commission. We compare space, insulation, ports, climate fit and system cost. If a cheaper tub clears the same system requirements, it can be the better recommendation.
Frequently asked questions
What size cold plunge tub should I buy?
Choose for body fit and space first, then use the actual water volume for equipment sizing.
Is an insulated cold plunge tub worth it?
If the water stays cold for long periods, insulation can materially reduce heat gain and chiller runtime.
Can any tub be connected to a chiller?
Not automatically. You need secure inlet/outlet plumbing, suitable materials and a loop that meets the chiller flow requirement.
Sources & data references
What to read next
Run your exact setup
Use your real tub volume, temperature target, climate, pump, filter and plumbing. ChillSizer checks thermal capacity and actual modeled flow together.
Open the System Designer