Does the cheato need to be spinning in the Tunze 3181 reactor to work properly? I put a small ball of cheato in and it was spinning for a short time now it is just at the bottom. The pump is at the same level as the reactor but I have about 3-1/2' of tube going in and 2-1/2' coming out of the reactor. I also have the pump turned up all the way. Thanks for any assistance. I just want to make sure I am doing this correctly.