Everything you need to know about hot tub flush

Posted by Nick Clamp in Maintaining a Hot Tub Guides on 21st July 2022

You can spend hours balancing your hot tub’s chemistry each week.

But if your spa’s plumbing is clogged up with grime, you’ll be fighting a losing battle. You’ll quickly run into problems like foamy hot tub water – and might even make yourself sick.

Enter hot tub flush…

© Villeroy & Boch

What is hot tub flush?

Over time, dirt, grime, and chemical deposits accumulate in the pipes your spa’s water is circulated through. Hot tub flush breaks this grime down and clears it out of your spa’s plumbing, keeping your spa clean and hygienic and its chemistry easy to balance.

How often should you use hot tub flush?

It doesn’t matter how fastidious you are about maintaining your hot tub’s water quality – it’s just a matter of time until sludge builds up in its plumbing. 

So, you should flush your spa’s pipes out every time you drain and clean it as part of your hot tub maintenance routine. This will stop it from ever becoming an issue that affects your hot tub chemistry – or your health. 

© Merlin Pools

How to use hot tub flush

Cleaning your hot tub’s plumbing with hot tub flush is quick and easy. Here’s the simple six-step process:

  1. Remove your hot tub’s filters (this is a great time to clean or replace those).
  2. Turn your hot tub’s jets on to full and open up all the air valves. 
  3. Add your hot tub flush to your spa, following the manufacturer’s instructions.
  4. Leave your hot tub to run with its jets on full for 15-30 minutes so the flush can circulate through the whole system. This will make your hot tub foam up, and a biofilm will start to collect along its sides (that’s all the grime that’s built up in its plumbing!).
  5. Drain your hot tub. While it’s draining, use the waste water and a cloth to clean the residue left behind by the flushing process.
  6. Once your spa is drained, it’s time to clean it, refill it, heat it back up, and balance its chemistry.

Then all that’s left to do is enjoy a well-earned soak in your squeaky clean spa!

© AquaVia

The final word

Hot tub flush is a must-have for hot tub owners. Your spa will become very unhygienic very fast if you don’t flush your hot tub’s plumbing every time you drain and clean it. 

Follow the simple six-step process we’ve laid out in this short guide to make sure your spa’s plumbing doesn’t become a big problem.

Looking for more hot tub maintenance tips? Grab your free copy of the latest edition WhatSpa? magazine for the latest guidance on how to get the most from your home spa and our picks of the best buys on the market today.

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About the author

Nick Clamp

I am the Editor-in-Chief at WhatSpa? Media Group and have been actively involved in the hot tub and swim spa industry for over 20 years. I fell in love with hot tubbing in 2002 and since then have dedicated my career to helping millions of hot tub buyers to make more informed choices when navigating their buying journey.

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