How to Drain a Hot Tub: The Complete Guide

Draining your Hot Tub

On the surface, draining a hot tub look at a pretty simple and straightforward process – but there’s a lot more going on beneath the surface, we can tell you that for sure.

Draining a hot tub every now and again is a great way to flush the water that you’ve been soaking in for weeks (maybe months) right alongside a bunch of other people. That is a big old pot of soup with plenty of dirt, debris, and oil mixed right in and can get unhealthy in a hurry even with regular shocks and proper treatment.

hot tub drain

Thankfully though, learning how to drain a hot tub isn’t going to take a whole lot of time when you zero in on the tips and tricks we highlight below.

We are going to share with you everything you need to know about draining the tub from start to finish, getting it cleaned and ready to be refilled, and helping you to avoid some of the unpleasant surprises that improperly drained and incorrectly cleaned hot tubs inevitably bring to the table.

Let’s get to it!

What’s the Value in Draining Your Hot Tub to Begin With?

As we highlighted just a moment ago, your hot tub is going to have the same water and it for weeks (and maybe even months) at a time – with all kinds of people dipping into and out of it on a regular basis.

If this was a bathtub (which is basically what a hot tub is, only on a giant scale) the odds are pretty good that you wouldn’t even consider dipping your toe in the warm water without knowing that it was perfectly clean, sanitized, and healthy to soak in.

Sure, hitting your hot tub with sanitizer and shocking it on a consistent basis is part and parcel with being a responsible hot tub owner.

At the same time, though, the water inside that tub remains the same – and eventually, all the chemicals in the world aren’t going to do anything to the dirt, debris, body oil, lotions, cosmetics, sweat and more that are building up inside of it.

A regular total drain from top to bottom is the only way to guarantee that your water is completely fresh, healthy, and ready to go throughout the entire hot tub season (or all year long, if you run your hot tub 365 days a year).

On top of that, a regular drain out of your hot tub is going to get rid of any of the biofilm that might have started to collect along the way.

Tiny bits of bacteria and fungus are always living, growing, and breeding inside of your hot tub plumbing. And while chlorine and chemical treatments are going to do a great job at keeping those issues in check, for the most part, it doesn’t take long for this bacteria and fungus to start to build up a natural defense against those heavy-duty chemicals.

Over time, biofilm starts to establish itself – rejecting chlorine and having it slide right by the bacteria and fungus that now is completely armored against those chemical cleanouts.

The longer that the biofilm stays inside your plumbing the more these contaminants are allowed to grow and reproduce, and before you know it you have a huge buildup of these issues that aren’t just tainting the water and making it unsafe to soak in. But they are actually gumming up your plumbing, breaking down water flow, and crippling your filtration unit as well.

It’s in these moments that a total drain out has to happen and even then you’ll have to use a special cleanouts solution to destroy biofilm wherever it might be found.

When is the Best Time to Drain My Hot Tub?

We aren’t suggesting that you have to totally drain your hot tub every month or so – or even every couple of months – but there are definitely some telltale signs that your hot tub water isn’t quite as healthy as it could or should be and should be swapped out for something new and fresh.

Some obvious signs and symptoms that your water is less than ideal include (but aren’t limited to):

  • Foul-smelling odors that aren’t chemical in nature
  • Your water just won’t become crystal-clear again, even after shocking it or treating it with a lot of chlorine
  • You’ve been using your hot tub on a more frequent basis (like every day each week or multiple times a day)
  • You’ve had more people in the hot tub than usual (especially after a party aware dozens of people might have taken a dip in the water)
  • Your hot tub has sat unused and unmaintained for an extended amount of time

If any of those conditions are something you are dealing with right now the odds are pretty good that a total dump out, deep clean, and refresh of the water in your hot tub is necessary.

On top of that, as a general rule it’s not a bad idea to consider draining your hot tub every three months like clockwork even if you aren’t experiencing any of the signs or symptoms we highlighted above.

The odds are pretty good that you’ll be using your hot tub on a somewhat frequent basis, necessitating a cleanout anyway, and three months is usually how long your hot tub can go before it starts to get a little bit “funky”.

It’s always better to dump out your water and refresh it too soon or too early rather than too late.

Stick to and every three-month schedule (draining and replacing water as necessary on an emergency basis) and you’ll be good to go!

How to Actually Drain Your Hot Tub

A lot of hot tub owners are under the impression that all they have to do to drain their hot tub is simply pull the drain plug and watch as the water comes flooding out – but that’s not exactly the entire picture.

For starters, you are going to want to make sure that you flush all of the plumbing lines in your hot tub before you dump out the water in the main tub compartment itself.

What you want to do is get your hands on specialty shock cleaners and drain out cleaning solutions that go right to work on biofilm, devastating and destroying all of the bacteria and fungus that could have otherwise exposed you to some pretty significant contaminants that can recharacterize your health and wellness.

This line flush product is going to circulate throughout your entire hot tub (including the core plumbing systems and your filter unit) for about 30 minutes or so, making sure that it kills all of the biofilm and the bacteria that has been using that film as a shield.

A lot of people go so far as to add another shock system to the swimming pool and allow it to circulate for 24 hours (and sometimes even longer), guaranteeing that their pool is going to be sparkling leak clean as soon as they dump out the rest of the water.

No matter how long you leave these chemicals set, though, the odds are good that you’ll begin to notice a nasty looking foam bubbling up on the surface of your water. That’s all of the biofilm and bacteria that were hidden throughout your hot tub rising to the surface, and all of that is going to be skimmed off and flushed away with this deep clean.

Now comes the easy part.

After you have added that chemical cleanouts solution all that’s really left to do is hook up a garden hose to the drain section of your hot tub, run it to an area of your property that you can flush this chemically treated water without ruining your lawn or endangering pets or your family, and that gravity handles the rest of the heavy lifting.

It’ll take a couple of hours for your pool to drain out completely (and you’ll want to make sure that you cut the power of your hot tub before you pull the drain plug) but you’ll be ready to rock ‘n’ roll in no time.

Of course, if you want to speed things up a little bit you could always drop a sump pump directly into your hot tub and have the water level dropped to nothing inside of a couple of minutes rather than a couple of hours.

It’s a good idea to stand close to your hot tub if you’re taking this approach, though, as you want to make sure that you aren’t burning up the motor on your pump as soon as it finishes the job.

Cleaning and Refilling Your Tub

The last piece of this puzzle is pretty straightforward.

There are a lot of products out there on the market today designed to help you deep clean your down dry hot tub, and you’ll want to take advantage of those products while you can to sanitize your tub before you add any extra water.

This is also a perfect time to swap out filter cartridges and components, clean off the shell of your hot tub, and take care of any other maintenance or repairs necessary before you start to fill your tub again.

The last thing you want to do is hook up a garden hose and then attach a filter to the end of it to avoid hard water and calcium making their way into your hot tub. From there it’s a set it and forget it kind of approach to get your water level back up – and then you are off to the races again!