Hi folks, my first time with a sourdough starter but my grandmother had one and I know the beauty of these little gems!
First, there are as many opinions and formulas for sourdough starters as there are humans on this planet, so I started with one that seemed to be most consistent: 1:1:1 ratio of whole wheat, water, starter.
All started slow but progress every day.
* Went from daily to 2x day feedings and didn't feed until hungry (when I saw legs)
* Everything smells great, looks great....no hooch except for day 3
* Proper consistent temperature...saw bubbles, rise and fall, etc.
Yesterday morning it passed the float test so YAY!! But then I fed it one more time to ready it for bread and all STOPPED. 8 hours later it barely doubled. I didn't feed it all day, waited until this morning and it had doubled. I fed it again this a.m. and it has barely moved since 8am (and it's now noon).
HELP!!!!
1) What did I do to my starter that was almost ready to go??
2) What should I do NOW???
I had a similar experience to yours, where my starter had taken off, looked great for 2 days of 2x/day 1:5:5 feedings, then everything nearly stopped again. I was terrified I'd somehow undone all my hard work getting it going, but it bounced back relatively quickly. I think in my case it just wasn't quite up to being fed that much and I overdiluted it, because skipping a feeding seemed to help.
This little hiccup in mine also came a few feedings after I stopped giving WW flour and went to AP flour, right around when the remaining WW flour was so diluted I no longer could see it in the culture. I suspect that change may have had something to do with it. Double check your routine to see if anything changed. New bag of flour? Even if it's the same brand it won't be exactly the same unless it was from the same batch. You forgot and used tap water when you've usually used bottled? Something I learned from keeping aquarium fish is that the additives that are in your tap water can change without notice. It is apparently common that more and/or different chemicals are added based on the season.
Also if you make a mistake (in measuring, or introduce a contaminant, or etc) in a feeding, it might take several feedings to get your starter sorted out again. I did this once! I just added extra water and I didn't think it would matter, since the food itself was correct. But my starter hardly bubbled at all. I think I was lucky that just 1 proper feeding seemed to get it sorted out that time. More established starters are supposed to be more resilient, but ours are young.
However, in your case, I wonder if those 1:1:1 feedings are not enough for it now that you have yeasts present. If you have a few containers available, you might try doing a few different, and bigger, feeding ratios. See which one gets it to the point in its rise & fall cycle you want it to be when it is time to feed next. From what I have read, a newbie is more likely to make the mistake of overfeeding in the early stages. Once the yeasts move in (which happens after the lacto bacteria move in), a newbie is more likely to make the mistake of underfeeding.
One more thing, I would guess that it having "barely moved" 4hrs into a 12hr feed cycle is not too bad. It will always be a little slow to react when you first feed it, and should gain momentum as you get further into the cycle. I read about people who get doubling in 2-4 hrs but I've never seen that. Trying to figure out how to get those really quick vigorous responses myself, now.