Hot Tub DIY From A Stock Tank Pool

Disclosure: We are not electricians. Please read how we turned our stock tank pool into hot tub at your own discretion. Always use/consult a certified electrician when installing your pool and pool heater. Always disconnect your pool pump and heater from electricity before getting in the water.

Well, it’s the first day of Fall, and folks are starting to shut down their stock tank pools. And while it’s always sad to see summer fade away, I know you are so excited about everything cozy. This is why we are excited to show you how we turned our stock tank pool into a hot tub!

Back in 2018 we turned our stock tank pool into a hot tub, and it was A LOT of work! We rigged up an electrical heater (we literally built the entire thing) and got our 8’ pool up to a nice hot tub temperature. The only problem was that it took SO long to heat up. I think we ran it for an entire day, or two, to reach that temperature. And all the while the tank was letting out heat. Anyway, it’s safe to say that it wasn’t very efficient. It did work though, and some of you may have even seen the tutorial before we decided to take it down this year.

The good news is that we have figured out something better that is pretty simple to put together. We used this spa heater we found on Amazon. It’s very affordable, but it doesn’t have a plug end, which is where an electrician comes in. The heater connects inline to our pool pump hoses and turns on when there’s enough water flow to trigger it.

We are using the Intex 1000 GPH pool pump and it was strong enough to keep the heater on. We read some folks reviews saying they had a pump that wasn’t strong enough, but ours is working perfectly. This means you could use this heater with a 1000 GPH or anything bigger. I would not suggest using a smaller pump.

If you need instructions on how to install the Intex 1000 GPH pump, check out our video by clicking here!

We were very impressed with how fast this heated the water, given our past with heating the stock tank pool. But there is one very crucial thing you must do no matter what you heat your pool with- INSULATE!

Let me tell you, the metal on a stock tank pool is not going to keep the heat inside your pool. It’s going to let that heat out almost as fast as it comes in. We decided we needed to make a koozie or jacket of sorts for our stock tank. To do that we used reflectix, a very thick wool rug pad, and flannel fabric. You don’t have to go this route- there are many ways that you could insulate your stock tank pool. However, you definitely need to do something if you actually want to use your stock tank as a hot tub. You also need a cover. We plan on making an insulated cover, but for now we are draping a tarp over it and it’s working just fine!

We turned our heater off one evening and the water was at 102 degrees. In the morning the water was 94 degrees. This means that this stock tank koozie/jacket situation actually works and is crucial for being able to keep your hot tub water warm. You definitely don’t want to have to heat your water from something like 52 degrees every time you want to use it.

If you don’t want to deal with electric (besides your pump, of course) you can always opt for a gas tankless water heater. This one is a great option as it heats more water faster than other ones and it is specifically made for being outdoors!

Okay, so you probably want to know how I connected this part to our pump, and I will do my best to explain. Please note that these are instructions for using the 1000 GPH pump. I will note how to alter for the 1500 GPH Pump or 2500 GPH Pump. Here are all the things I purchased:

• Spa Heater

• 1.5” PVC Pipe

• Type A Hose Adapter

• Type B Hose Adapter (comes in a set, but only need 1)

• Swimline Adapter

• Silicone Sealant

• JB Weld Marine Weld

• PVC Cement

• A Good Thermometer

Step 1. Cut your PVC into two parts. I used a mitre saw and my pieces are 10” each.

Step 2. Attach the Type A Hose Adapters to the PVC. These fit on the inside of the pipe. You need one on each piece of PVC. I originally used sealant on to seal these two pieces, but the water pressure was too high on one side. I ended up using JB Weld Marine Weld on that side. I followed the instructions and then put the material on the outside of the adapter and the inside of the PVC pipe and let the pieces cure.

Step 3. (Skip this step for 1500 or 2500 GPH pumps.) Create the extra piece for the pump hose to connect to. I took a Swimline Adapter, cut off the section with the threads with a mitre saw, then sanded the edges. I then took Type B Hose Adapter and cut off the lip on the smaller end. This took some finagling but some wire cutters did the job best. I then fit the Type B Adapter into the Swimline adapter. It’s a tight fit, but I used Marine weld again to secure them to each other.

Step 4. Attach your PVC to the heater with PVC cement. Follow the instructions on the kit. The PVC pieces will fit right into the pieces attached to the pump.

Step 5. Once everything has cured for the correct times, it’s time to attach the heater section to the pool pump. Turn your plunger valves to the locked position. Disconnect the hose from the lower outlet plunger valve. If you have a 1500 or 2500 GPH pump, you will completely remove the hose and replace it with the new heater section. If you have the 1000 GPH pump, you will connect the hose to the extra piece from step 3 and then attach the heater to the plunger valve and the extra piece now attached to the hose.

Turn your pump on to make sure there aren’t any leaks and everything is flowing smoothly. If you heater is connected to electricity safely, it will automatically turn on when your pump flow water through it. So you’ll just sit back and relax and wait for the water to heat.

If you turn your stock tank pool into a hot tub this season, we’d love to see your pics! Tag us on Instagram @stocktankpool for a chance to be featured!