I also used it about a week ago when I was out of rotifer diet. I guess it worked they lived. I've also read you could use yeast to feed the rotifers until you needed to use them for fry then you need the good stuff for the fry to do good I think you have to give them the good stuff for at least 4 hrs before you feed them to the fry.
I used the yeast in one culture it now has white stuff floating at the top.

I'm not sure how much of it to use. I'll have to see if any of them lived or if I killed them. I cannot remeber the site where I read about the yeast.

I wish I could it would be alot cheaper.