How to Drain a Hot Tub and Clean It Completely Like a Pro

Michael Keenan


Hot Tub Maintenance

Most pool owners avoid draining their swimming pools as much as possible. Because the volume of an average hot tub is so much smaller than a pool they are much easier to drain and then clean thoroughly.

Hot tubs also run at higher temperatures than pools and so have even better conditions to harbour unwanted bugs and germs so draining them is recommended from a health point of view.

Stick with me and I’ll explain how to drain and clean your hot tub the easy way!

Hot tubs seem like mini swimming pools. But their maintenance is quite different. While pool cleaning requires a lot of water, it’s not the same with hot tubs.

They are small enough for you to do regular maintenance without feeling like you’re wasting a lot of water. And regular maintenance is necessary so that contaminants don’t take over your tub. Here’s a look and what you need to do and how.

drain your hot tub for cleaning

Quick Answer:

Draining a hot tub is an essential part of maintenance and should be done regularly. It involves cleaning the lines, turning off electricity, draining the water, and scrubbing before refilling.

Depending on the design you own, your actual draining method will vary. For example, most have a drain plug which can be used in conjunction with a submersible pump to speed things up. Additionally, line flushing products are available to clean out any biofilm and other nasties that may have accumulated in the plumbing pipes over time.

Finally, after your hot tub has been drained and scrubbed it’s important to either clean or replace filters before refilling with fresh water.

Why You Need to Clean Your Hot Tub Regularly

It is important to clean hot tubs that are indoors and outdoors to avoid scum and dirt and to keep the water safe! But if your tub is outside the house, you want to keep it clean and protect it from dry leaves, the trash that comes with the wind and maybe even excrement from animals, depending on where you live.

Nobody wants green water in their hot tub!

The waterline and the seats must be maintained for a clean hot tub and avoid water issues. Typically, a weekly cleanse with a sponge and white vinegar is good enough. Use them on the shell of the tub and also the jets to keep them in good shape. Make sure you scrub on all surfaces to remove the scum.

While the weekly rule is great, the inside of a spa must be cleaned as often as possible. That includes wiping down the shell after a good scrub and rinse.

Now, you might also want to quickly cover it with a 10 percent bleach solution while you’re down there doing the dirty work (well, it’s not really dirty if you don’t let it get there). This keeps the mildew in check. It can also help get rid of calcium deposits and biofilm that cause white flakes in a hot tub.

A hot tub is clean and you will be happy in it if you go through this routine once a week. See my guide on cleaning a spa without draining it first for some useful tips and tricks I use all the time.

clean hot tub outside

Why Drain Your Hot Tub or Spa?

Draining your hot tub, on the other hand, is at least a quarterly exercise. It’s something that needs to be done once in every three or four months. You’ll have to do it more frequently if you use it more or have guests. But once in 3 – 4 months is a must even if you use it less than usual.

As I mentioned before, because your hot tub runs at higher temperatures than a swimming pool it can be a breeding ground for pests and diseases . Draining it every so often and starting with nice fresh clean water is just good practice. For some problems like white mold, you’ll need to drain the tub to give it a chemical clean.

The easiest way to do this is to create a timetable for maintenance. This has the weekly duties, quarterly tasks and the annual maintenance activities. That way, you will never forget another session. Remember that in cold climates it is good practice to winterize your hot tub if it isn’t going to be used regularly in colder months.

How to Drain a Hot Tub

The actual draining method will vary depending on the design of hot tub you own. It is a similar process to draining an above ground pool but with a few extra steps.

The first step should be to clean and flush the lines in your hot tub. You know all the plumbing pipes that circulate the water and give you those lovely bubbles? Well they can get pretty messed up with algae, biofilm and other nasties.

Before you actually drain your hot tub, flush the lines using a line flushing cleaning product – there are loads to choose from and they don’t cost too much. If you skip this you’ll regret it! You add the product and then run your hot tub for a while to circulate the cleaner.

When it is flushed you should make sure the electicity is all turned off – no nasty shocks!

Next you can drain your hot tub. Most tubs have a drain plug but you can use a small submersible pump to speed up the process. Be careful what you do with the waste water – in some cases it must go into a sewer to keep with local laws.

Once your hot tub is drained you can get to the scrubbing part! Don’t forget to give your filters a clean or replace them if needed before you fill up again. See below.

Tips to Keep Your Hot Tub Clean

Then comes the how. Once you know when to do it, you should shift focus to what to do with the hot tub and how to keep it good enough to make it inviting. Here are a few tips that will keep your cleaning regime in check.

Water Chemistry

The most important thing to do is to keep the water chemistry in check one or two times a week. If you leave them unchecked, you risk destroying the plumbing system and also the water in the hot tub.

There are all kinds of test kits and strips that are easily available and make sure you check the water chemistry of your spa regularly. See my guide on how to test hot tub water quickly and easily.

The ideal levels should be 80 to 120 ppm alkalinity, 7.4 to 7.6 pH levels, 1 to 3 ppm sanitizer and 150 to 250 ppm calcium hardness.

Shocking Your Hot Tub

Shocking the water is a process of adding extra chlorine to the water of a hot tub or a pool to kill contaminants and algae in the water. This is because not all contaminants can be killed by the regular dosage of sanitizer.

Experts say this must be done once a week at least to keep it clean and healthy. If you have a pool, you can use the same stuff to clean the hot tub too. And you can use chlorine or non-chlorine sanitizer to get the job done.

Be sure to read the instructions on the packaging of the product to find out how much sanitizer must be added to clean a hot tub of your size. The logic is not the same as a swimming pool, so you must be careful with the quantity.

You must also make sure that none of it touches your skin because some products have the tendency to cause burns. Also, remember to leave the pump running so that the water can circulate in the spa and distribute evenly.

hot tub filter

Don’t Forget the Filter

While cleaning the surface of the hot tub, remember to clean the filter too. The cartridge, which is usually located under the skimmer basket, must be entirely removed and cleaned once every four to six weeks.

After the cleaning, please remember to hose it well to remove traces of all cleaning materials. This makes sure that the surface does not suffer rust or rotting, depending on the materials that the spa is made of.

Carrying out this exercise once every four to six weeks is the perfect amount of time. And experts say you must replace the filter cartridge once a year to make sure your hot tub is healthy and isn’t allowing bacteria and algae to grow.

Fill ‘Er Up

To keep your hot tub full for as long as it is turned on is an excellent practice. If you don’t have it filled up to the skimmer line, your hot tub will end up sucking air into it and might just damage the pump and the heater.

Don’t Forget about the Cover

A hot tub is something that takes good care of you. So you should do the same, whether it is indoors or outdoors. One of the most important things when it comes to easy maintenance steps is to keep a cover on it when you’re not using it.

This is particularly useful if it is outdoors. This way, you can keep not just the contaminants out but avoid dry leaves and other dust that the wind brings along. And don’t forget them animals lurking around to take a poop in your lovely little spa.

hot tub with a cover


What materials do I need to safely drain and clean a hot tub?

To safely clean a hot tub, you will need a suitable bucket and/or container, a hose for draining purposes, cleaning supplies such as sponges or brushes and specialized hot tub cleaning chemicals.

Is it necessary to use any special cleaners or chemicals when draining and cleaning a hot tub?

Yes, it is important to use the correct cleaners and chemicals when cleaning your hot tub to ensure that it is effectively sanitized. On the other hand, some people swear by houshold cleaning products and even use vinegar as a cleaner. I prefer the real deal.

How long does it usually take to fully drain and clean a hot tub?

Depending on the size of the hot tub, draining and cleaning usually takes between one to four hours.

Wrapping Up

Now you know how to drain a hot tub – keeping it clean is not that hard. But neglect it and you will end up with a big container full of gunk. Maintaining it is slightly tougher than taking care of a bathroom but a lot easier than keeping a swimming pool clean. You need to find a balance between the two.

To summarize, what you need to do is keep an eye on the levels of water chemistry and clean it once a week. Then you must give it extra chlorine treatment or shocks once a week too.

Test the water frequently and use a quality hot tub sanitizer – perhaps have a look at some alternative hot tub sanitizers here. Maybe when your tub is drained and cleaned, it could be a good time to consider converting to a saltwater hot tub. See that guide and learn how a saltwater system could save you time and money. And be more eco-friendly!

While you’re at it, don’t forget to rinse the surface of the tub and clean the filters well. You must also replace the filters once a year.

Then there is the question of keeping enough water in the hot tub when you’re not using it so that air pockets are not created in your plumbing. That can lead to all kinds of problems. And finally, get a good cover that fits your spa well and keep it on whenever you’re not using it.

A little bit of all this can make your spa time not just a time of joy but will also save you the trouble of illnesses. And don’t forget, if your hot tub is seeing more action than usual, you will have to work that much more on keeping it clean and presentable.

Last update on 2024-06-17 / Affiliate links / Images from Amazon Product Advertising API

michael keenan author

Author - Michael Keenan

I'm Michael Keenan the owner and creator of the Outdoor Care Guide. I'm a trained horticulturist with over 30 years of experience in pool care, plant care, and landscape care! Seemed like a good idea to share - I think I can make your life easier and save you some time and money!