DIY Insulated Stock Tank Hot Tub | Insulate to Conserve Propane and for Comfort | Built to last |

With an outdoor temperature of 40°F and starting with a water temp. of 104°F this hot tub experienced only a 1/2 degree drop per hour over 24 hours. It took 17 minutes to heat the hot tub back to 104°F after heater being off (I let the filter run 10 hours a day) and cover on for 24 hours.

Total cost to operate hot tub in March was .65 cents a day. Filter draws 52.4 watts for 10 hours a day, the heater pump draws 150 watts and runs an hour a day max, based on how often we use it. Cost to fill the propane tank was $22.00 and lasted 41 days. Electricity cost here is 15.23 kwh.

The stock tank is a 6 foot trough stock tank from Lowes (This one is a Tarter brand), the actual water capacity to where we fill it is about 105 gallons. The actual dimensions and water capacity on these tanks is smaller than advertised.

I used grey silicone to seal around the tank and FOR SAFTEY seal with silicone the top of the corrugated metal where it meets the wood and the ends of the tank where the metal meets the tank to avoid any sharp edges or gaps.

The seats are Intex 28502E PureSpa Non-Slip Removable Contoured Seat for Inflatable Hot Tub Spa Accessory with Adjustable Heights and work perfectly.

Here is the channel for the info on the heating side of the hot tub. ‪@stocktankpools4980‬
   • Stock Tank HOT TUB DIY Guide (propane)  
I got the idea for the heat control from ‪@StockTankPool‬ .
It is a DIGITEN DTC101 Temperature Controller Digital.
The heater I am using is a Camplux DB158.
For the Filtering side of the system:
(2 of these) FibroPool Pool Return Jet Kit - You will need to make new or modify the gaskets to work on the stock tank.
(1- 2 pack of these)ATIE 1.5" 90 Degree Elbow Pool Hose Adapter Fitting SPX1105Z3 Replacement for Above-Ground Pool Pump
(Pump) INTEX C530 Krystal Clear Cartridge Filter Pump for Above Ground Pools: 530 GPH Pump Flow Rate.
Extra filters (Pack of 6) Intex 29000E/59900E Easy Set Pool Replacement Type A or C Filter Cartridge.

I used 1 tank (20#) of propane in February before the cover was done, it lasted about 3 weeks. (I was using 1" foam for the cover) It was mostly above freezing at night and 50s in the day. The last tank was on the tub for 41 days. (March, no freezing temps highs in 50s and 60s).

The cover is 3 layers of 1" exterior foam insulation with foil bubble insulation on the bottom and the corrugated tin on the top.

The roll fiberglass is r-13
The outer sides is 2" exterior foam sheeting.
I used 24" Foil bubble insulation against the tank and bottom.

To plug the filter in/outlets if I need to work on the pump without draining the tub I screw 2 1.5" mpt plugs into the in/outlets (loosely).

I turn the unit off or turn the temp down when I am done using it. If the flame were to go out while heating, the pump would continue to run and eventually burn out because I don't believe this heater has a re-light function if the flame in the heater goes out. The propane turns off, it is just that the pump would continue to pump cold water.