Andrew - we're all flying blind here, because you've made such a hash of the start, we can't make your wine taste good. But we'll try and save some of it, if we can.
Can you take a hydrometer reading of the 17.5l batch and let us know what it is please.
Starting measurements: brix 16.7% , SG 1.070 (roughly only able to make 9.19%ABV if fermented to FG=1.000)
no record
21 oct measured: SG = 1.010 , Brix = 5.7 - 5.9% (most probably affected by alcohol produced) , PH = 2.7
21 oct night measured: 5.1% brix, added 250g white sugar, brix become 7.1% ( the goal is keep adding 250g sugar until yeast can't take it anymore).
23 oct measured: SG = 0.997, Brix = 5.6% , Taste test: unpalatable, bitter sour..
23 oct added in 500g white sugar
23 oct measured: SG = 1.016, Brix = 8.6%, taste test: at least taste better; not so unpalatable.
no time.
26 oct morning, added in 200g of white sugar without measuring. **no time to check**
26 oct evening, sieved out grape pulb because all color has already leached out .
26 oct evening, measured: 16 liter of wine. SG = 0.996 PH = 2.7 taste test: taste much like watered down juice.. weird. but smells fruity.
26 oct add in 400g sugar (just to keep it going, hopefully)
26 oct switch to air lock
i think my goal for this is to make it as high as possible until the yeast stopped.. then i back sweeten it just enough .. I don't think i want to use any chemical to stop it at specific ABV.
Can you tell me how much sugar to add each time (drip feed) for a liter of "juice" , so won't hinder the yeast ? and also not over the board ? seems to be 500g is still ok to it for 16 liter .. ..but usually how much sugar / liter ?