We are novices to having a pond - and this will be our first winter with a nicely stocked pond.
We have a 16000 ltr pond - with 24 fish ( all approx 6-7 inches long)- mixture of mainly ghost koi, 4 shubunkins and 6 goldfish.
We are a little concerned at the moment that we are getting conflicting advice on what to do for the best over winter - some people are telling us to switch everything off once the water gets to approx 45deg
Other people are telling us exactly the opposite
I can understand that freezing cold water can damage UV filters (we have a huge Yamitsu Mega Black box with UV filter - which I certainly would not want to damage!!!)
Can someone please come back to me with the best way to over winter a (mainly) koi pond - as I need to make sure that I will have fish in spring!!!!
Just leave everything on, it'll be fine. As stated the plants will die off, but dont worry they will grow back, unless they are floating in which case they will need to be taken indoors over winter.
I tend to switch those fancy fountain heads over to something like a foam nozzle, it breaks the water up a bit more and stops it freezing. Aslong as the pond is more than 3ft deep your fish will all be fine.
If the pond does freeze over, be sure to put a hole through the ice so the poisonous gasses can be released out.
Dont have a clue about UV, never had one, so you'll have to wait for someone else to reply, sorry!
I leave everything running apart from the UV, and the only reason I turn that off is that its not doing anything during the winter. The running water from your filter return will stop a portion the pond surface from freezing. Somepeople will tell you move the pump up in the ater so that a layer of warm water will stay at the at the bottom of the pond. In fact water has to VERY deep for this to make any difference. When the water temp drops below 10 stop feeding your normal food and move over to a wheatgerm based food, or try brown bread. Alternativly stop feeding altogther. As water temp drops fish can not digest fod very well and it will sit and rot in the gut. As long as you have fed well during the warmer months the fish will have enough fat reserves to see them through the winter. As the weather warms a little next year, give your filter a good clean, in pond water, and turn the uv back on. Start to feed samll amounts as the fish become more active, but remember that most, if not all, of your bacteria will have perished during the winter and the filter will in effect need to mature again. Dont hesitate to ask any more questions,we are here to help.
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