100% hyradtion

for the record, I keep my Rye starter at 150% hydration... After using it and topping up the jar it will be a bit looser after a day in the fridge though.

-Gordon

Rye flours (especially dark rye flour) requires much higher hydration levels that AP flour to achieve the same consistency. The "gumminess" of rye dough is probably due to the high level of pentosans in rye flour. These gummy carbohydrates are broken down over time when subjected to an acidic environment, which is provided by lactic acid bacteria (LAB) in the starter sponge.

can be carried over to your sourdough bread dough.  If mixing a dough by feel. you will notice the dough loosening up as it ferments.  That is the major reason for many sourdough recipes to incorporate folding the dough during the bulk rise to maintain dough shape and keep it from turning into a puddle of dough.  

Rye "gluten" structure is a weak one that has a stricter working time than a wheat dough. It falls apart much sooner and rye dough gets stiffer at the same low temps as wheat.  When retarding or chilling rye starter, you will also notice it can rise and dome and maintain that dome even after the starter below the surface has long fallen to the bottom of the starter jar creating a hollow space.  In a loaf, that would be over-proofed.  So it never hurts to poke the starter while observing it.

Sifted fine flours tend to absorb less water than their whole grain counterparts.  Whole grains tend to ferment faster.  Rye will also ferment faster than wheat and when mixed with wheat shorten overall wheat dough fermenting times.  Wheat will lengthen rye fermenting times.