Starter problems after refrigeration
I'm new to baking with sourdough, and I made my first starter three weeks ago (100% hydration, 50/50 rye and AP flour). I keep it in the fridge when I'm not baking, feeding it twice a week (or 2 times during 24h before baking). I notice that it rises to about double it's size in approx. 10 hours on the counter after feeding it, lots of bubbles, at which point i put it back in the fridge. A few hours later it's dropped considerably, almost back to where it was. Is it normal for this to happen so quickly in the fridge?
I don't know if it's my fridge or the starter itself, but I've had some trouble getting the two breads I've made with it so far to rise after the overnight cold fermentation. According to Reinhart in BBA, the dough should then rise to about double it's size within 4 hours on the counter. Mine was pretty much the same after 8 to 9 hours, no oven spring, flat (yet tasty) bread. My kitchen is fairly warm, about 75 to 77 °F. Perhaps my fridge is too cold for any fermentation to happen while in there, but should the yeast not "wake up" again during a final proof of 9 hours art room temp?? The "barm (Reinhart) doubles in size, the final dough shows some growth (although it takes a few hours longer than the recipe states). Then nothing. It seems like the real problem occurs after refrigerating...
I'm really confused now, thinking I might have to skip the cold fermentation altogether 😔