I started my sour dough starter on Friday evening using 175g strong white flour and 175ml tap water and mixed with 4 chopped up green grapes. (I'm following Paul Hollywood's sour dough starter recipe here).
By Sunday it was bubbling away so I thought everything was fine. On Monday the bubbling had died down and so I decided to feed the starter by discarding half of it, and adding in 100g flour and 100ml water. I gave it a good stir and put it back in the jar. Since then, no more bubbles, and a layer of liquid has formed on top of the starter (see picture). According to the recipe I'm following it is supposed to be good to use in a dough now, but since it isnt bubbling and looks like not much is happening, I'm scared that its dead.
Should I risk using it in a dough or just start over?