Perfect prep machine question

[KatyN]

I read the instructions through the other day and it says to put the water in first and then the formula.. Is there any reason for this!? I was wondering if I could fill the bottles with formula before I go to bed and then top up with water as required!
Thanks kx

In my experience powder will go rock hard quite quickly if you take it out of the box and store it in the bottle. You could always store the powder in a special dispenser to use when needed. Or you can take your Perfect Prep machine upstairs with you at night to use.

I think it's because it doesn't mix well, and it can spray the powder about (back onto the machine) thus making it less sterile.
So - not mixing well can lead to lumps, which won't be sterile throughout.
Back-splash of soggy powder clumps end up sitting on the machine, and can breed bacteria.
I think - I'm not a scientist!

As owl suggested, we use the PP machine over night, but make it fresh with the kettle/tap in the kitchen during the day.