The rhubarb wine has now been sitting quietly for a couple of months - it stopped fermenting ages ago & it has been happy to be left to its own devices to sloooooowly clear, leaving a slight layer of pale sediment on the bottom of the demijohn.
The sediment will taint the wine if it's left in the demijohn too long, so it's time to siphon off the good clear stuff into a bucket & discard the yuck.
Once the clear wine has been safely siphoned through the tube into the bucket, the next stage is to de-gas the wine - when CO2 gas is locked in the wine, it is said to affect both the taste & appearance of the wine, although it does dissipate over time.
De-gassing wine involves shaking it all about vigorously & splashing is back & forth between demijohn & bucket a number of times in order to release any carbon dioxide gas present.
The wine ends up back in the demijohn with a teaspoon of potassium sorbate & a crushed campden tablet - a belt & braces measure, these chemicals stopping any possibility of further fermentation in the bottles.
Any sediment should appear & settle out quickly, & it will be ready to bottle in a couple of weeks.
Oh - do remember to have a taste, but don't be surprised if its not perfect at this point - it will need a good six months in the bottles where further magic will transform it from simply alcoholic fruit juice into something really rather good.