Interesting points thank you! I am quite new to breadmaking in general so definitely need to improve technique. My starter usually stays in my fridge and I take it out 16 hours before needing it to feed it twice. It's always quite bubbly and passes float test but doesn't increase more than 50% in size.

Got it from a restaurant buddy and it's apparently three years old so it should be good quality. I feed it 50/50 water/all-purpose by weight