How to Drain and Refill Your Hot Tub - Step-by-Step

Many Tucson homeowners have a hot tub or spa, and they love the benefits that these bring to their lives. You get an opportunity for relaxation, you can gather with family and friends, and allow the stress of the day to simply float away. 

However, a hot tub or spa also needs to be maintained, and part of that maintenance is draining and refilling it as necessary. Even with filter cleaning and the correct chemicals, over time, the water in a hot tub will diminish in quality. Knowing how to clean and change hot tub filters can be beneficial. To keep water fresh and healthy, it's recommended that hot tub owners purge the water and drain it every three to four months. Here's a step-by-step guide to drain and clean your hot tub.

Why You Need to Drain Your Hot Tub, Clean Your Hot Tub, and Refill Your Hot Tub

Even when you use chemicals like chlorine and bromine, run hot tub filters, and keep up on other maintenance, the hot tub's water or water in the spa eventually needs to be drained and replaced due to becoming saturated with contaminants and minerals. Replacing your hot tub or spa water ensures the following:

• Clean, fresh water 

• Improved lifespan for equipment

• Easier chemical balancing

• Healthier environment

In Tucson, where many residents have hard water, draining and replacing the water is even more important. Here is a step-by-step guide:

Step 1: Gather Supplies Needed to Drain a Hot Tub

The best way to start is to gather all of the supplies you will need. So, when it's time to clean your hot tub, collect the following: 

• A sump pump or hose to drain out the dirty water

• A wet/dry vac to remove any leftover water and to blow water out of the plumbing

• A mild, non-abrasive hot tub cleaning product (not household cleaner)

• Soft cloths or sponges

• Hot tub chemicals for rebalancing the water

• Test strips

Step 2: Power Down the Hot Tub or Spa

The next thing to do is to turn off the power to the hot tub or spa. You don't want to have electricity and water mixing, nor do you want your pumps and heaters running without water flowing through. 

Step 3: Drain the Hot Tub Water Using a Submersible Pump or Hose

There are two main ways to drain a hot tub:

Use the Drain Spigot

Most hot tubs have a drain spigot or a drain valve. This is usually near the base. You can attach a hose, open the valve, and drain the internal part of the tub. This takes a longer time to drain, but it is also a bit easier. 

Use a Submersible Pump

Using a pump is a faster way to drain the hot tub, and it can usually empty the water within 15 to 30 minutes. 

Keep in mind that no matter which way to drain your hot tub you choose, you want to make sure to run the hose away from your house, your landscaping, or anyplace that can flood.

Step 4: Remove Leftover Water and Biofilm

Even after you drain most of the water out, there will still be a little water in there. If you leave it in there, you can create a biofilm, which will lead to bacterial growth. Use your wet/dry vac to suck out any remaining water, and then towel-dry areas that are visibly wet.

Step 5: Clean the Hot Tub Shell With a Safe Cleaning Product

When the water is out of the hot tub, it's a great time to give the shell a good cleaning. Only use hot tub cleaner or a vinegar and baking soda solution. Don't use household cleaners, as they can leave residue that will clog up the filter or pump. 

Step 6: Inspect and Clean Filters

Filters play a crucial role in maintaining water clarity. While the hot tub is empty, remove the filters and rinse them with a garden hose. For deeper cleaning:

• Soak them overnight in a filter-cleaning solution.

• Rinse thoroughly before reinserting.

If filters are frayed, torn, or over a year old, it may be time to replace them.

Step 7: Refill the Tub with Fresh Water

After cleaning, it’s time to bring fresh water back in so you can use your hot tub. Place the hose into the filter compartment rather than directly into the tub. This helps push water through the pipes, reducing the chances of airlocks forming in the system.

• Fill the tub until the water level is above the highest jets.

• Check that the hose filter (if available) is used to reduce hard water minerals, especially important in Tucson.

Step 8: Restore Power and Prime the Pumps

Once the hot tub is filled, restore power at the breaker or control panel. Many hot tubs require “priming” the pumps after refilling to ensure proper water circulation. Follow the manufacturer’s instructions—this usually involves running the pumps briefly to push air out of the lines.

Step 9: Balance the Water Chemistry

Fresh water needs proper balancing before the hot tub can be used. Test strips should be used to measure levels and adjust accordingly:

• pH: Aim for 7.2–7.8.

• Alkalinity: Keep between 80–120 ppm.

• Sanitizer (chlorine/bromine): Maintain safe levels based on your preferred system.

• Calcium hardness: Helps protect equipment from corrosion.

Adding chemicals one at a time and retesting ensures accuracy and prevents adding too much.

Step 10: Heat and Enjoy

After balancing, allow the hot tub to heat up to the desired temperature. This may take several hours depending on the model and size. Once the water is warm, the hot tub is ready for use again—this time with clean, fresh, and inviting water. Spa maintenance Tucson may be be able to help.

Use this Step-by-Step Guide or Call a Professional

While many homeowners in Tucson handle draining and refilling themselves, there are times when professional help is best:

• When water consistently turns cloudy or foamy.

• If scaling or mineral deposits are severe.

• When equipment malfunctions after draining.

• For those who prefer hassle-free maintenance.

Professional hot tub service ensures proper care and prevents costly repairs down the line. E-Konomy Pool Service & Supplies has been helping Tucson pool, hot tub, and spa owners for decades. Call now for more information.