thank you all for replying on my question about my pond it was really useful,thanks once again

hi you could always leave the pump running 24 hours if you wish. if you put a tennis ball in the pond this helps a little bit for oxygen for the fish but what ever you do dont brake the ice the shock will kill the fish. pour some hot water slowly to melt a hole in the ice other than that. good luck.

I always take my pump out of my (French) pond and let the ice form...the fish go into a sort of suspended animation at the bottom of the deepest part during the coldest weather. Doesn't seem to do them any harm and last Spring they had loads of babies. But I only have hardy fish...

the only problem is that toxins can build up under the ice if its frozen for any length of time, our pump runs all the time-- a piece pf polystyrene that you can remove each day for a while can help but agree not to smash a hole or the shockwave will damage the fish

I would keep the pump running--as long as it isn't attached to a fountain or waterfall--to keep an area of surface from freezing.