For how long can I keep the Mash before distilling

[Hal]

Can someone please advise for how long can I keep the mash before distilling it?

My specific situation:
Grapes mash, I have fermented few buckets in my house at a temperature of around 22 C with loosely opened lids.
Not sure if fermentation is completely done, but it looks like it is - it has been almost 3 weeks.
It takes 2 days without mixing for the skins to get up to the top. I don't see any bubbles, maybe a few in the corners....I got some wine out and the Brix was 0.99

Should I continue to store this with loosely open lids inside?
Is it better to move it in the shed where the temperatures are 10 C on average with closed lids?

I should distill it in a week or two, when I get a Pot or make it myself

[Sailman]

What I would do would be to rack it off the sediment and then store it in a sealed container. As long as there is enough CO2 still escaping from your must it will create a protective barrier on the top. I personally wouldn't let it sit too long. Also be careful if there is a lot of CO2 escaping it could blow the lid off of your container without a vent.

[Hal]

Does it need o be stored at a specific temperature? Outside or Inside?

By sediment do you mean skins? Should I not use the whole mash for distilling? Can I add water to it?

Thank you

[still_stirrin]

....I should distill it in a week or two, when I get a Pot or make it myself.

Maybe you’ve put the cart in front of the horse.

When you get, buy or build a still, you’ll need to do a few cleaning runs first. For example, 1st a good water/steam run, then 2nd a 50/50 water and vinegar run, and finally 3rd a sacrificial alcohol run. These are recommended to clean out any residual building materials than may be toxic. It is our standard of excellence recommended to keep new hobbiests safe.

So, your fruit must ferment will have to wait in line for a while to run.
ss

[Demy]

There are some visual indicators on the end of fermentation for example the solid part will go to the bottom (if heavy enough), there are no more bubbles that rise, if you mix there will no longer be a release of fizz etc ... to be sure just measure . Towards the end of the fermentation it is best to cover your ferment.