G'day Lyndall,

Yes you can, Platypus suggests laying it half-full on its side in freezer with all air removed.It is important that you don't overfill it as water expands as it freezes and this can burst your bottle

G'day Heather,

We've had a look at this for you and we think it wouldn't quite work. The entire lamp section needs to be submerged in the water, but the neck of this bottle is too narrow. We'd suggest going for a wide mouth style bottle to ensure the water is adequately purified by the UV lamp.

Platypus doesn't openly advertise this Hal, but I have heard of people using their Platypus soft bottle as a hot water bottle.

There are a few things I would recommend though.

Firstly, I wouldn't use boiling water - warm to hot might be a safer bet.

Secondly, I'd suggest using the closure/screw cap version for this to ensure it is a leak-proof as possible.

Lastly, I probably wouldn't fill it up too much just to minimise the instance of pressure building up and causing a leak.

The only other thing I would mention is to proceed using it this way with caution. I personally don't like putting bottles of water in my sleeping bag, particularly down, as in the small chance that it does leak, your sleeping bag will lose all insulating properties. It may be worth using it to warm the bag up initially, then take it out so no leaks occur overnight whilst you are sleeping.

That's just my two cents worth, others may have a differing opinion.

G'day Tegan,

Platypus does not recommend washing in a dishwasher and I've found that when using only water in the bottle, they can simply be rinsed with warm water and are fine.  The following is the company's washing instructions: 

Use hot, soapy water and rinse thoroughly with hot water. For tough cleaning jobs, add 1/4 cup of baking soda to 3/4 cup of water per liter volume of your bottle or reservoir and shake for 30 seconds. Add 1/4 cup lemon juice, shake 10 seconds, and vent by loosening cap away from face. Repeat shaking and venting three times. Expel as much air as possible, cap bottle, and allow to soak 20 minutes. Rinse three times with hot water. Caution: When adding lemon juice to baking soda, effervescence occurs and will cause pressure to build in a capped Platypus product.

G'day Anne,

Platypus advises that you can freeze water in these if you are careful to ensure all air is purged and that they are not entirely full to avoid explosions when the water expands.