How to Remove Sand from a Hot Tub (and Stop It Coming Back)

Updated September 2026. I’ve tidied this up and added the causes I’d check first (including a faulty sand filter), options for shop-bought acrylic tubs, a safety note on using the jet pump as a vacuum, and how to stop the sand coming back. My favourite trick for DIY tubs, using the skimmer as a vacuum, is still here.

Sand and grit in the bottom of a hot tub is one of those small annoyances that drives owners mad. You clean it out, and a week later it’s back, crunching under your feet on the seats. The good news is that it’s easy to get out, and usually easy to stop.

Here’s where it comes from, the best ways to remove it for both shop-bought and DIY tubs, and the method I recommend to my DIY build customers.

Where does the sand in a hot tub come from?

Work out where it’s coming from first, because the fix is different for each:

• Feet and swimwear. This is by far the most common cause. Sand, soil and grit from the garden, beach or patio get carried in on feet, especially if the path to the tub crosses a lawn or gravel.
• Blown in. Dust and grit get in when the cover’s off, particularly on a windy site or near a sandy border.
• Your sand filter. If your tub runs a sand filter and you’re finding more than a sprinkle, especially near the return jets, the filter may be leaking media. Leslie’s says lots of sand usually means a broken lateral or standpipe inside the filter. Small amounts can come from a faulty multiport (backwash) valve or an overfilled tank. A little sand straight after a backwash or re-sand is normal.
• New surfaces. On a freshly built tub, fine dust and grit from render, grout or tile adhesive can wash out for the first few weeks. Brush it and let the filter catch it. If it carries on for months, look at whether the grout or render is breaking down (low pH or very soft water will do that).
• Things that look like sand but aren’t. Undissolved chemical granules and flakes of scale can look like grit. If it disappears after a few hours, it was probably granules. So pre-dissolve granules if the label says to.

A correction: the old version of this post said sanitising chemicals “often contain sand particles”. I can’t back that up, so I’ve taken it out. Undissolved granules and scale are the more likely explanation.

How to remove sand from a hot tub: your options

Method	Best for	Pros and cons
Handheld battery spa vacuum	Acrylic spas, quick weekly clean	No hoses and easy to use. Needs charging, and small debris bags need emptying.
Hose-powered (venturi) grit vacuum	Small amounts of grit	Cheap. Adds a little water, and fiddly for big jobs.
Skimmer vacuum plate and hose	DIY tubs with a pool-style skimmer	Uses your own pump and filter, and costs very little. Needs a compatible skimmer.
Wet/dry vacuum	When the tub is drained	Gets everything. Only practical at a water change.
Brush towards the skimmer or drain	Light dusting	Free. Slow, and heavier sand just settles again.
Drain and refill	Only if it’s due anyway	Wasteful of water, heat and chemicals just for sand.

I still wouldn’t drain a tub just for sand. It wastes water, chemicals and all the energy you’ve put into heating it. If a water change is due anyway, though, that’s the perfect time to get the wet vac on the floor. See how to drain and clean a hot tub.

How to use your skimmer as a hot tub vacuum

If you’ve got a swimming pool, you’ll know you can vacuum it through the skimmer, using the pump’s suction. You can do exactly the same on a DIY hot tub fitted with a concrete pool skimmer. This is how I recommend my DIY build customers vacuum their tubs.

My personal favourite skimmer is the Certikin HD100, and it’s the one I use in most of my DIY builds. It’s still widely sold in the UK. If you’re still at the planning stage, there’s more on fitting one in how to install a skimmer on your DIY hot tub.

What you need

• A skimmer vacuum plate. For Certikin skimmers, that’s the HD103 “Kornea” vacuum adaptor plate. When I first wrote this it was around £15/$20, and it’s still about that in the UK. It sits in the skimmer and forms an airtight seal, so the pump’s suction is diverted to a 1.5in hose tail.
• A length of 1.5in (38mm) vacuum hose. It’s really a flexible hose rather than pipe, just like the hose on your vacuum cleaner at home.
• A vacuum head is optional. I don’t bother (see below).

Step by step

1. Make sure no one is in the tub. You’re about to put the full suction of the pump through one open hose. That’s fine for grit, but never for fingers, hair or kids. See the safety note below.
2. Switch the pump off and fit the vacuum plate in the skimmer, following the plate’s instructions. Some sit in place of the basket and some on top of it.
3. Prime the hose. This step is really important. Feed the hose into the water so it fills completely, or hold one end over a return jet until water comes out of the other. You want a hose full of water, not air.
4. Connect the full hose to the plate while it’s still under water, so no air gets in.
5. Turn the pump on high. On my own tub, the circulation mode just doesn’t give enough suction. The hose floats about and does very little. Put the jets on high and the suction kicks in.
6. Work slowly across the floor and seats. I just use the end of the hose, no vacuum head, and it works like a charm. It’s a little hard to see with the jets running, but the end result is a sand-free tub.
7. Switch off, remove the plate and refit the basket.
8. Rinse the filter. All that sand is now in your cartridge (or sand filter). See how to clean a hot tub filter cartridge.

Why priming matters

If you connect an empty hose and switch on, the pump sucks a hose-full of air straight into the system. That can airlock the pump, and a pump running dry can damage its seal. If it does happen, see how to deal with a hot tub air lock.

A safety note

Suction outlets in hot tubs can trap hair and limbs, which is why modern drain covers are designed to prevent it. A single open vacuum hose on a powerful jet pump has none of those protections. Only vacuum with the tub empty of people, keep hair and hands away from the hose end, and switch off before removing the hose.

What about shop-bought acrylic spas?

Most acrylic spas don’t have a pool-style skimmer you can fit a vacuum plate to, so a dedicated spa vacuum is the way to go. Battery-powered handheld pool and spa vacuums with a fine-mesh bag or filter are the easiest option. There are also cheap hose-powered grit vacuums for the odd handful of sand. Look for one with a fine filter bag, so the sand isn’t just stirred back into the water. A household wet/dry vacuum is only worth using when the tub is drained.

How to stop sand getting in

• A mat, foot tray or foot rinse by the steps. It’s the single biggest fix. There’s more on getting in and out in hot tub steps: the ultimate guide.
• A clean path from the house to the tub: paving or decking rather than grass or gravel.
• Keep the cover on when the tub isn’t in use.
• Rinse off after the beach or gardening before getting in.
• Keep the skimmer basket and filter clean so they keep catching grit. There’s a routine in my beginner’s guide to hot tub maintenance.
• Service a sand filter if it’s shedding media. Check the laterals and re-sand with the right grade. See a deep dive into sand filters, and if you’re choosing, cartridge or sand filter?

Parts and planning

You’ll find skimmer parts, vacuum plates and spa parts at parts4tubs.co.uk in the UK and parts4tubs.com in the USA. And if you’re planning a build, a pool-style skimmer is one of those small decisions that makes life easier for years. It’s part of the plumbing layout in my DIY hot tub plans, and the full build is in my DIY in-ground hot tub build guide.

FAQs

Why is there sand in my hot tub?

Usually it’s carried in on feet or blown in with the cover off. If you have a sand filter and you’re finding a lot near the return jets, the filter may have a broken lateral or standpipe.

Can I use a normal vacuum cleaner on a hot tub?

Not a household dry vacuum. A wet/dry vacuum is fine once the tub is drained. With water in, use a spa vacuum or a skimmer vacuum plate.

Can I vacuum a hot tub through the skimmer?

Yes, if it has a pool-style skimmer like the Certikin HD100. Fit a vacuum plate, prime the hose with water, and run the pump on high. Only do it with no one in the tub.

Will sand damage my hot tub?

Mostly it’s a nuisance, but it clogs filters, can scratch acrylic if it’s ground in underfoot, and wears pump seals if lots of it gets past the filter.

Do I need to drain the tub to get rid of sand?

No. Vacuum it out instead, and save draining for your normal water change.

Found a better way to keep sand out of your tub? Share it in the comments below. I read them all.

Cheers,
Andi

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Hi, Andi here. I own Buildahottub.com and also write all of the articles and info pages on the site. Some years back now, I built my own hot tub but struggled to find the information I needed. So, once my tub was complete, I started this website to help others in their own pursuit of hot tub and plunge pools DIY building information.

Fast forward to 2025, I've helped over 1400+ DIY customers just like you all over the world build hot tubs and pools. Have a good look around the site, there are lots of resources here. Please do get in touch if I can help you. - Cheers, Andi