We are all pond lovers and enjoy the water features that we add to our gardens. Different strokes for different folks. I would fill your pond with water asap. Give it time to settle in and observe over the winter.
I keep mine running 24/7. I had a bio filter to help hold and disperse the natural elements to maintain a natural balance in each pond. I removed them and it didn't seem to make much difference once the ponds were balanced.
I never shut the ponds down as long as the pump is working the flow of water is moving they have never frozen. I put in a larger than needed pump in for this reason.
The koi are air suckers and in winters hibernate and they have nice covey holes to hide in that raccoons cannot reach. Something to consider if adding fish they keep skeeters away. I also have Plecostomus fish or catfish are bottom feeders they are great for debris at the bottom.
In my experience any plant you add will adjust before winter and go dormant . They will be fine if added later this season once water is balanced. They are all still on their own natural calendars when winter comes.
It's always a learning curve as the water and plants adjust. The bright sunny 😎 days of summers and warm temps will have its issues with water moss..algae. If you are considerin g a green pond that's ok or like a clear pond. Either way there is a balance once everything settles and adjusts over time.
Hope this helps a bit.
Anxiously awaiting this pond construction to be complete.
