5l water bottle as demijohn

[Spring Heeled jim]

I see Asda are selling 5l water for 50p.

I'm thinking of buying one to use as a demijohn.

Question is, do I need to drill a hole in the top to fit a grommit and airlock?

Or could I get away with screwing the lid on sufficiently enough that it doesn't pop off while fermenting but loose enough that it allows CO2 out?

Cheers

Jim

 

[Parva]

Just leaving the lid loose enough to allow C02 to vent off is perfectly fine. :)

 

[Wez]

Putting some cotton wool in the neck works good too.