How Do You Deep Clean a Hydro Flask?

Sometimes you’ve left your Hydro Flask too long between cleans or you’ve left a smoothie or old coffee and let it go bad in your Hydro Flask and it needs a deep clean. So how do you deep clean a Hydro Flask and get it back to brand new?

To deep clean a Hydro Flask you need to do more than just give it a light wash in warm soapy water. You want to get rid of all the build up as well as kill any germs, mold or bacteria that may be growing in your Hydro Flask.

Here’s how to deep clean a Hydro Flask and get it as close to brand new as possible.

To deep clean a Hydro Flask soak the inside in vinegar then use baking soda to give the inside a good scrub as well as the lid. Alternatively use bottle bright tablets, dry rice or a magic eraser to deep clean the inside.

In this article I’ll talk more about these different techniques and you can choose the method that you like best so you can give your Hydro Flask a deep clean.

The Easiest Deep Clean Method: Bottle Bright Tablets

If you’re lazy (like me) and don’t want to put in a lot of effort to soak and scrub and work hard to give your Hydro Flask the deep clean it needs then the best method for you is going to be Bottle Bright tablets.

These are tablets that are designed to give the inside of your Hydro Flask a solid clean for you.

The main ingredient is hydrogen peroxide, baking soda, citric acid and salt…plus a few other plant based agents like cellulose.

You simply put the tablet in your Hydro Flask, fill it up with water and then the tablet will fizz and dissolve in the water and clean your bottle in the process.

Once it’s completed then it’s always a good idea to give your Hydro Flask a good scrub with a tough bristle bottle brush (see the best bottle brushes for Hydro Flasks) to remove any residue and then give your bottle a good rinse with water before using it.

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The Natural Deep Clean: Vinegar and Baking Soda

Vinegar and baking soda are great natural cleaners so if you want to avoid using any harsh chemicals then these two natural cleaning products are the best way to give your Hydro Flask a deep clean.

The vinegar is acidic which helps to dissolve and clean away any residue that has built up. Lemon juice is another acidic cleaner that you can use if you’re like me and don’t like the smell of vinegar.

Put some vinegar in your Hydro Flask and close the lid and give it a good shake so the vinegar covers all surfaces of the Hydro Flask. Also take the lid off and soak the lid in the vinegar so it gets a good clean too.

Then make a baking soda paste with baking soda and water, or baking soda and vinegar. This becomes your abrasive cleaner.

Put a clump of the paste on your bottle brush and then go for it. Give the inside of your Hydro Flask a solid scrubbing, making sure to get in everywhere even under the neck where the bottle curves up.

Then give your Hydro Flask a good rinse with water and leave to dry. Repeat this process if you need to give it an ever deeper clean.

Another Lazy Deep Clean Method: Dry Rice and Water

Another lazy method to deep clean your Hydro Flask is to put some dry rice in the bottom of your Hydro Flask.

Then put in a bit of water, vinegar or water + detergent. Close the lid and shake that bad boy like you’re in a band and it’s the final encore song.

Give it all your might and shake it hard in all directions for 1-2 minutes or even 5 minutes if your arms can handle it.

Give it to the kids or your friends and get them to go for gold and shake it baby shake it!!!

The dry rice will impact the sides in all directions and act as an abrasive cleaner, cleaning off the residue and leaving the stainless steel sparkly and new.

For an even better result soak the inside of the Hydro Flask in boiling water or in vinegar first to loosen up the grime so the rice can more easily remove it.

Deep Clean Polish: Using a Magic Eraser

You may want to use an abrasive cleaner to clean the inside of your Hydro Flask and to give it a good polish.

This will remove any stains on the inside of your flask and leave it shiny and as good as new.

I personally recommend avoiding steel wool if you can as tiny flakes of steel can come off and this can lead to rust on the inside of your bottle.

Use a magic eraser instead. These are made from a special type of plastic/foam that happens to be a micro-abrasive cleaner.

This will rub away any imperfections or build up mold or grime and leave your Hydro Flask shiny new without the worry about it rusting.

It can be used on the outside of your Hydro Flask too but do it gently and be careful as it does have the potential to remove the paint.

Get a Magic Eraser at Amazon

Make Sure To Deep Clean Your Lid

Hydro Flask lids also get dirty and mold can form under the rubber gasket in the lid.

To give your Hydro Flask lid a deep clean you’ll want to remove the rubber gasket carefully using a knife and then using vinegar or some other cleaning product and give both the lid and the rubber gasket a good scrub to remove all the mold.

Then rinse the parts and leave them to dry separately before reassembling them.

How To Clean Rust From Your Hydro Flask

If you’re Hydro Flask has built up some rust over time then don’t stress too much.

While not super common this is definitely something that can happen if you don’t take good care of your bottle. Learn more about if and why Hydro Flasks rust.

The easiest way to clean rust from your Hydro Flask is to fill it up with Coca-cola.

How NOT To Deep Clean Your Hydro Flask

When you’re giving your Hydro Flask a deep clean there are a few things you should definitely NOT do. If you do these things you will likely cause your Hydro Flask some serious damage.

Don’t Put Your Hydro Flask in the Dishwasher

You might think a great way to deep clean your Hydro Flask is to throw it in the dishwasher and let the dishwasher do your dirty work for you.

Unfortunately, Hydro Flasks are not dishwasher safe.

The intense heat and water pressure of the dishwasher can damage the vacuum seal, causing your Hydro Flask to no longer insulate properly. This means it won’t keep drinks cold or hot effectively anymore.

The dishwasher can also negatively affect the paint on the outside of your Hydro Flask and cause discoloration, which isn’t pretty.

So yeh, don’t put your Hydro Flask in the dishwasher.

Don’t Use Bleach

While bleach can be great for cleaning a lot of things it is terrible for cleaning Hydro Flasks.

Bleach (and chlorine) actually react with stainless steel and cause it to corrode and get damaged.

Given Hydro Flasks are made from stainless steel, bleach will cause damage to your Hydro Flask, so don’t use it.

More on can you use bleach in a Hydro Flask