In-pond filter
operates on suction side of pump, bogging pump over time.
Frequent removal of filter for
cleaning disturbs debris around filter.
Filter location at lowest dissolved
oxygen level in pond. Lack of oxygen at 
filter minimizes aerobic biologic filtration.
Filter and pump hardware combination
in pond is unsightly.
Externally located filter provides
for easier access, less time to clean, isolated from
pond and tends to be more aerobic.
|