If the anemones foot was injured,it wouldn't be opened up.
Leave the pump off. Maybe even lower the pump to the bottom of the tank and the anemone move itself.
+1 Yote!!! My RBT Anemone got shreded a koralia. I removed the torn tenticles from the tank & placed the powerhead/nem @ the bottom in hopes that the nem would move to a more lit location & it worked!
Also agree with Yote! My anemone was completely sucked into a powerhead and I assumed it was gone. I left it in to see what would happen and it made a complete recovery and lived for a quite a long time (I guess it made him tougher..LOL..)