last a year i started with a 100g ( and a gnat stove + evernew 550 pot used both as a pot and as a mug )

i bought a new 100g canister in Braemar but it was only for safety and turned to not being needed


but i had 3 evenings meals and 2 breakfast without boiling water
and i dont cook , just tea , cafe , soup, dehydrated meals
no porridge at all !!!

if you want to be sure easiest way, ( will spend a canister )
take a new one,
weight it,
burn it to ( if a 100g )-25g /-50g /-75g / empty on your scale.
each time put it to float in water and draw a line
you can reproduce this on a new canister and have an easy way to check precisely whats left in during the challenge.
( unless its way under 0°C and you dont burn the gaz melange evenly...)