Powering a fountain/filter for a container water garden?

from my experience one has to have a pump going 24/7. this keeps the water flowing and if the pump has a built in filter it also keeps the water clean. occasionally you may have to change the water as depending on how much sun your container pond gets it will have some degree of green water which is algae. the snails help to keep the algae that grows on the bottom and sides of your container cleaner,but a good filter is a definite plus. check with your local Earl May or where ever you are getting the container pond from. Sometimes less is better when it comes to small container ponds as you are wanting to do.