Starter Hit and Miss

Toast

I’m two weeks into my sourdough journey. I’ve baked bread with it twice and had a nice rise both times. What I’m not understanding is the rise of my starter. At first I was feeding every 24 hrs, now I’m down to every 12 hours. Finally got it to double 3 days ago, but today it didn’t. And it never really looks spongey. I’m feeding AP flour 1:1:1. Any suggestions or thoughts are appreciated! 

It'll be fine - just give it a couple more weeks :)

At present the environment inside the culture will still be developing, with different nutrients becoming available due to the presence of metabolic byproducts; and some species of yeasts yet to appear. Stick with it...

If I were you, I would stick to feeding once a day but with a lower proportion of old starter. Otherwise you'll find yourself having to treat the darn thing like a demanding pet (!) Personally my preference is that once the starter is established I keep it in the fridge and only feed it the day before I'm planning to bake; unless it's been in there unused for more than two weeks at which point I'll "let it out to play' for a bit...