Nope, no filter needed. Without critters you won't have the water getting
soiled, and since you plan to have plants in the water, you will be filter
the water naturally. I would suggest however that you include a filter in
your future plans. Once you have a water garden, you'll no doubt want fish
some day.

BV.



Thanks! Knowing me, I think you're probably right... some day I'll want to
do more. Maybe frogs from behind our house will relocate to our pond.

Lydia