I am currently on day 4 of the levain starter from Peter Reinhart's Crust and Crumb and have growing concerns. The only difference from the recipe is that I used all wheat flour for day 1 and then half wheat and half white for day two then all white for days 3 and 4. Day 1 was just fine, there was a significant amount of growth and it smelled like strong sourdough. After day 2, the starter had quadrupled in volume, hit the plastic wrap covering the container and collapsed. Day's 3 and 4 were pretty much identical, there was no rising and no visible bubbling. The starter has the normal, sweet acidic smell of a sourdough. Days 1 and 2 were quite warm and very humid (mid atlantic heatwave): upper 80s/low 90s and 50-70% humidity, days 3 and 4 have been in the mid to upper 70s and not humid at all.
Should I be concerned that there is no longer any visible rising? The instructions for Day 4 say that the levain starter is ready once it triples in volume. Should I have used the starter after day 2? Should I toss it out and start over?
Thanks for any help!