Question
how often do I clean mud out of my ponds?  

Answer
Hi,
it all depends on what you want if you want  clear water you will have to clean it out on a regular basis if you want a natural pond and all that goes with it ,not very often,
But you will find that koi keepers have crystal clear water so that they can enjoy the colours of their koi and also to check if any of the koi have any damage or disease.
You can visit my pond at http://koi-z-are-us.20m.com
George.