I've lovingly made my sourdough started and it's all gone to plan. So today, I moved to the next step of making the sponge (I think that's what it's called) to make a loaf with tomorrow. I know I supposed to wait 24hrs but I've had a sneaky peek and although it is a bit bubbly, it as a film of wateryness on top. Is this just a stage or has it gone wrong?
I used mineral water to make the starter but tap water to make the sponge. Does that matter? I know you are not supposed to make the starter with mineral water as the chlorine in tap water messes with the yeasty process, but does this apply to making the sponge and then the rest of the loaf? Making the starter with mineral water is one thing but using it for the whole loaf....