We are about to install a large pond in our garden. We don't intend to keep
fish in it, but do want to keep the water clear.

The advice we have received is that we need a UV clarifier to prevent algae
formation but, as there will be no fish, there is no need for a filter to go
with it. The algae will clump together and settle to the bottom.

However, looking here, it seems to suggest that a filter is needed - does
anyone have any experience and if so can you let us know. I don't want to
make an expensive mistake and install the wrong system.

Many thanks in advance.

Harry