I don’t know anything about ponds. If I did, I would write a short post here about why it is important to keep your pond maintained through the winter months and how to do it.
It wouldn’t be a very long post. Anything from 100 to 300 words. I would use a little formula that went something like this.
Attention grabbing statement such as “If you don’t keep your pond looked after throughout the winter you will pay the price in the springtime.” Or something more positive like “How to keep your fish healthy and well during the winter”
Then I would put the substance of the post in. Something like. When it’s cold and dark outside it is easy to forget about your garden. But if you have a pond or water feature, it is important to maintain them throughout the Winter to avoid problems caused by the elements. I’d then describe one of the problems that can be caused by lack of maintenance.
Then maybe some facts or figures or a little story to illustrate the point.
Then what jobs they need to do during November. Or get you round to do on their behalf.