Caring for your Koi fish in the fall does not apply to all climates or weather regions because some regions simply do not have the season fall. At the commencement of fall, in September, the weather tends to be more like summer conditions and you will want to treat your Koi as if it were summertime. It would be unlikely that you would have high enough temperatures in early fall to worry about fin rot, sunburns or other heat related conditions, but it is always possible. < ?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office"/>
Just remember that in warmer weather, ideal temperature conditions for Koi fish are between 78 and 84 degrees. Anything privileged than that and your fish start to have issues. But in most areas in early fall, temperatures of high seventies would be scarce. As it gets colder and the temperature dips below 68 degrees, you can start feeding your Koi a bit less. Feed them about twice a day at this temperature. Once it goes below 65 degrees, you can cut back to feeding your Koi once a day and start cutting back on how much protein you feed them. Start mixing in staple foods with wheatgrass and anything else that is simple to digest. Once it hits 50 degrees, feed your Koi only every other day with wheatgrass. And the next step down is 45 degrees, where Koi fish commonly stop eating altogether. Once the temperature is reaching this low, Koi need to conserve their energy and their metabolism slows down. When you start reaching the shortly months of fall, like November and December, the climate tends to be more like winter conditions and can be treated as such in regards to your Koi.
If your pond starts to reach freezing levels on a regular basis, take note of this and make sure you are monitoring your fish appropriately. Koi fish are cold water wish and deal very well with these conditions. You want to make sure that if it is a pond that goes below ground that it is at least two feet deep to account for freezing. Ice is ok but you do not want your pond to really freeze over. If you have an privileged than ground pond, you want to allow for even deeper water because you do not have the insulating effect of the surrounding soil. Other factors to consider once it gets colder are that your bio filter does not work very effectively, and levels of ammonia and nitrites will start to build up.