Matt,
I'm so glad the kreisel is working out...this is awesome man! My seahorse babies are doing very well, so you and Renee can have ALL of my luck!
With the little experience I have in raising clown and seahorses, I think the kreisel should be turned off. Being as the mandarins don't have fully developed eyes, I'm sure they hunt by tracking the tiny vibrations of the pods and rotifers. My thinking is that this will be easier for them in still water, but I don't KNOW anything about this.
My LFS got a wonderful looking pair of mandarins in, and I have them on hold. Not sure I'll ever get a spawn, but dangit I just HAVE to try now.
Congrats on an incredible thread/experience man!
Good luck Renee, we are all rooting for YOU now
Jason