Starter and hydration

Hi all. This is my first post on this forum but I've been baking bread for awhile - especially given that I'm working from home a lot more. I have a starter that is very robust and I keep it at 100% hydration. My question is how do I incorporate the water in the starter as part of the hydration ratio? I generally aim for 70% hydration by weight and I use 12% starter. I use the over night fermentation method but I continue to end up with an unruly dough that wants to resist shaping for proofing. 

Any thoughts?

Thanks

Mark