Jacuzzi J-345 size guide
Key figures
The Jacuzzi J-345 is built around 370 gallons of water. It occupies 84 by 84 inches with 36 inch walls, holds 6 people by its rating, and reaches about 5,021 lb filled and occupied.
Jacuzzi J-345 spec sheet
- Fill volume370 gal
- TypeHard-shell
- Dimensions (in)84 x 84 x 36
- Footprint49.0 ft²
- Rated seats6
- Gallons per seat62
- Water weight3,086 lb
- Empty weight825 lb
- Filled + 6 adults5,021 lb
- Standby heat (est.)8.3 kWh/day
- Heat-up 55 to 102 F (est., 4 kW)10.6 h
Formula-based estimates throughout the energy rows: 102 F held, 50 F outdoors, average cover, idealized heat-up.
Sizing it against the market
Market position: the hard-shell median runs 383 gallons and 88 inches. Against it, this model measures up with 3 percent less water than the norm and a body 4 inches narrower than standard. Water per seat: 62 gallons.
Full weight on the ground
Everything below the waterline is weight: 3,086 lb of it from the fill alone. Add the 825 lb cabinet and a capacity crowd of 6 (about 1,110 lb) and the pad carries 5,021 lb, some 102 lb per square foot. Work out any tub on the filled weight calculator.
Keeping it hot: the cost
Every day this spa quietly burns about 8.3 kWh holding 102 F against 50 F outdoor air (average cover). Your utility rate decides the total: $30 at $0.12, $43 at $0.17, $63 at $0.25 per kWh. Model your own rate and climate on the running cost calculator.
Additions for this water volume
Take these numbers straight to the scale; they assume the 370 gallon fill. Ounces by weight.
| To do this | Chemical | Amount |
|---|---|---|
| Raise total alkalinity +10 ppm | sodium bicarbonate | 0.89 oz |
| Raise free chlorine +3 ppm | dichlor granules | 0.26 oz |
| Raise bromine +3 ppm | bromine granules | 0.25 oz |
| Chlorine shock (+10 ppm) | dichlor | 0.88 oz |
Refine in the dosing calculator
Add in small steps with the pump running, wait, then retest before adding more. Never mix chemicals together, and always follow your product label, which wins over any calculator.
Owner logistics
Ownership rhythm at this size: top up water lost to splash-out, test a couple of times a week, and drain and refill the 370 gallons a few times a year. None of it is hard if the tub sits level, drains somewhere sensible, and has a dedicated 240 volt circuit installed by an electrician nearby.
Source
Capacity here (370 gallons) comes from the manufacturer's published specification, via jacuzzipartners.com. Manufacturer handbook. Average fill 370 gal; full spa volume 460 gal. Seats 5-6. Capacities vary with how high you fill and with seats and footwell; confirm against your own manual or a metered fill when precision matters.