The external pump's pre-filtering is on the outside of the pond and people tend to empty the basket more often because it is more convenient plus the pump itself is not sitting in the sludge on the bottom of the pond. The external pump tends to last MUCH longer before needing any repairs or replacement. The CAL Pump carries a 1-yr. When a part goes out on an external pump it can be replaced quite easily. If, let's say, the impeller goes out on a submersible pump that pump goes into the trash and another pump purchased to replace it.
External pumps are one of the most important components of low-maintenance pond design.
This can be done in just a few moments. Heavy and wet submersible pumps must be lifted from the bottom of the pond and cleaned at least once a week during pond season. This can become a major problem for senior citizens and others who can't lift heavy loads. The Doc's top gun line of external pumps. Excellent choice for large waterfalls.