Kevin, I have had the same results as Nicole, keep 'em clean, and harvest 50% daily. Even with 50% harvesting, my culture density increased rapidly. The females live for almost 2 weeks, but only reproduce for a few days, and it's early in their life span. If you don't harvest, you end up with old rotifers that eat all the food, but don't reproduce (from Randy Reed).
I have been using (secretly stealing) Nicole's bucket method in addition to a 10 gallon continous culture. The buckets are cleaner with less work, and provide back-up in case I destroy a culture. Another week of this, and I bet all of my cultures will be in buckets.
Nicole, not to jinx you or anything, but isn't this the dreaded 9th day? I hope all is well with them.
Jason