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How to clean your hydro flask for tang-free hydration

A person holding a Hydro Flask.
Hydo Flask

Hydro Flasks are insulated water bottles that serve as the ideal hydration companion for every occasion, whether you’re hitting the trail, getting your sweat on at the gym, or trying to cut back on the soda you drink in the office. Naturally, if you use your Hydro Flask a lot, you’ll need to keep it clean.

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Difficulty

Easy

Duration

10 minutes

What You Need

  • Bottle brush

  • Lemon juice

  • White wine vinegar

  • Baking soda

Even if you’re just using your Hydro Flask for water, you can still end up with a funk that tastes like you’ve filled up from a pond—to say nothing of the lingering taste that develops after drinking coffee or juice out of it. If you want to remove the taste and tang of old drinks or keep your water pure and fresh, here’s how to clean hydro flasks properly.

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Hydo Flask

How to clean hydro flasks for fresh tasting water

Getting your hands on a proper Hydro Flask cleaning set — consisting of a bottle, straw, and lid cleaning brushes — can help you to clean your Hydro Flask. When you’re cleaning a flask or any hydration packs you must use a clean brush. Seriously, keep a separate cleaning setup just for these. You’ll thank us for it.

Step 1: For general cleaning, pour 1/2 cup of distilled white vinegar into your flask. Swill this around and leave it to sit for five minutes before rinsing it with warm water. Repeat this if necessary.

Step 2: If you don’t want to use vinegar, you can use Lemon instead. This is an excellent cleaner with anti-microbial agents. Squeeze half a lemon into your Hydro Flask and fill the rest with warm water. Leave for half an hour, rinse, and leave your flask to dry.

Step 3: For stubborn stains or tangs — think black coffee — mix 2-3 tablespoons of baking soda with a small amount of warm water to make a paste. Dip your bottle brush into this paste and scrub your Hydro Flask with it to remove the stain. Rinse with warm water and remove all the paste remnants before use.

Here’s what you shouldn’t do to clean your Hydro Flask

If you want to keep your Hydro Flask in great condition, you need to know the best way to handle it. First of all, never store your Hydro Flask inside the freezer. Instead of cooling your drink, it will deteriorate the condition of the bottle. This is because the double-wall vacuum insulation of the Hydro Flask protects the temperature on the inside. If you want colder drinks, put some ice cubes in it instead — you’ll be surprised that they barely melt even after a lot of time has passed.

Another important thing is that when you clean the cap, no matter what type of cap you have (flex, wide-flat, stainless steel flap, or loop), you should avoid putting it in the dishwasher. Dishwasher soap can easily get stuck in the cap’s smaller areas, which can lead to mold or affect how your beverages taste. To clean your cap properly, hand washing is still preferred. Use hot, soapy water, rinse the cap thoroughly, then let it air dry. You should also avoid using chlorine or bleach when cleaning your Hydro Flask because it can affect the bottle’s stainless steel. Hydro Flasks, when properly cleaned and maintained, can last for a long time.

With a sparkly clean Hydro Flask, you can stay hydrated without health risks. Remember to wash your flask regularly for the purest hydration possible.

Frequently Asked Questions

How do you clean the inside of a Hydro Flask?

There are three proven methods for cleaning the inside of a Hydro Flask:

  1. Pour 1/2 cup of distilled white vinegar into your flask. Swill this around and leave it to sit for five minutes before rinsing it with warm water.
  2. Squeeze half a lemon into your Hydro Flask and fill the rest with warm water. Leave for half an hour, rinse, and leave your flask to dry.
  3. Try using a Hydro Flask cleaning set—consisting of a bottle, straw, and lid cleaning brushes—with warm soapy water.

How often should you clean a Hydro Flask?

While we recommend cleaning your Hydro Flask after every use—particularly if you drink anything other than water out of it—this might be excessive for you. At the bare minimum, you should clean your Hydro Flask once a week, to rid it of bacteria and lingering tastes.

What happens if you don’t clean a Hydro Flask?

If you don’t clean your Hydro Flask, it can build up bacteria—and even mold—over time, especially around the rubber seal under the cap. This bacteria can potentially make you sick, so we recommend cleaning your bottle after every use if you can.

Is it OK to put a Hydro Flask in the freezer?

It’s important never to store a Hydro Flask in the freezer, as it will deteriorate the condition of the bottle by breaking down the lining of the walls. If you want to use your Hydro Flask for a colder drink, we recommend putting ice cubes in.

Tom Kilpatrick
Former Contributor
A London-born outdoor enthusiast, Tom took the first ticket out of suburban life. What followed was a twelve-year career as… Read Full Bio
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