My starter (Sourdough starter from San Francisco that is supposedly 150 years old, so they say) has been a bit sluggish over the last few months. I'm still getting a nice crumb, but the starter is just not that active when I feed it- getting about maybe 20-30% growth at the peak.
Typically, I feed it 2x a day and had been following a 1:4:5 feeding, but have been recently trying a 1:2:2 on the first day from the fridge, and then 1:3:3 (50:50 wheat and white) for 3-4 days leading up to my levain.
I know starter feedings are very subjective, but does anyone have a rule of thumb on how to get this starter a bit more active? Should I be introducing more wheat? Adjusting the ratio?
(I just fed the starter this AM, but can share a pic later today after it begins rising)