I am totally new at sourdough and making my starter. I think that I am succesfull at it since my bread does rise nicely and have a great crumb.

However my bread is very Sour.I have a feeling that I am using too much starter as a percentage of my receipe. I read somewhere that I can substitute 15gr of dry yeast by 240 gr of starter. That is exactly what I have been doing

What is the quantity of starter that I should use for 700 gr of flour?

Thanks in advance for your input.

Dan