Autumn pond maintenance
Listening to the news today it's been reported that the UK has had the longest period of warm weather on record. I doubt this is all to do with global warming and sooner or later things will get back to normal. Now then, if you haven't done so already, is the time to get your koi pond ready for when the cold does eventually arrive.
The koi are definitely benefiting from the warmer weather as they continue to feed, but this should be reduced and only once or twice a day. Feeding koi a wheatgerm based food helps their digestion and the lower protein reduces any waste that the filter has to cope with. As the temperatures drop and your koi become less active so do the bacteria we rely on so heavily to keep the pond healthy. Luckily for our koi the growth of bad bacteria is also slowed but to help prevent any problems we should remove the sources of pollution before they can get a chance.
One of the biggest headaches this time of the year are leaves falling in the pond. They seem to be hanging on to some of the trees later this year, as though they like us are not quite ready for this weather to end. The most effective way to keep leaves out is to cover your pond with a weather proof cover or net. These both provide benefits but to some they can prove unsightly and not practical with every shape and design of pond.
The option then is to regularly remove them yourself or with a skimmer. Most leaves floating on the surface won't cause many problems and can even look rather nice, something the Japanese take great delight in, but if left to build up they can block pumps and later decompose effecting water quality. One variety of koi the Ochiba Shigure is even named after its appearance resembling dead leaves on a pond.
If you don't prevent the leaves from entering your pond then make sure the skimmer is regularly emptied or alternatively remove them yourself with a net everyday. This can be a pain but if removed now come spring you will have less problems to deal with. The greatest risks are leaves settling at the bottom or in quiet areas and then turning stagnant. A pond vacuum is very useful for this as well as cleaning out any other areas of the pond that collects dirt. There are a number of bacterial products that claim to remove waste and mulm from a pond before winter, but what needs to be remembered is that they will be less effective the colder it gets and should never be a substitute for good old fashioned cleaning.