Advice/opinion needed

[In2Caps]

I have a small backyard pond (~1,000 gallons--about 6x8 irregular, 24" deep). I have an external bio filter (built from a heavy duty 30 gallon garbage can) that that feeds a waterfall using a 2400GPH Pondmaster pump. I keep an aerator running year round, and a smaller Pondmaster pump (500GPH) that runs the UV sterilizer when the pond is "active." External bio filter/pump get shut down during the winter, of course, but I've seen such conflicting information about whether I should or should not be running a pump during the winter. I do have a deicer (and the aerator). I live in northern Virginia (outside DC). While it can get pretty cold here on occasion, not usually in any sustained way that there is any risk of a more than a thin layer of ice (with the deicer, never completely covers the pond). I have two very large koi (had then since they were very small; enlarged the pond because of them). Perhaps 20" long. (Nothing of value, except sentimental. I love them.) A couple other smaller former feeder goldfish and one shebunkin. All of which have wintered in the pond at least one season.

My fish definitely go dormant for several months, but I have usually kept a small pump running (about halfway below the surface). I am now questioning whether that is necessary or even prudent. My primary goal here is to improve the odds of my fish surviving (as they have for several years). If running a pump does that, I will--but I have been reading very conflicting opinions on this and if it is a BAD thing (or even neutral), I'd be thrilled not to have to do it. I question it every year . . .

Thanks for any advice!

Karen

 

[MitchM]

The only reason that anyone should have to shut off their pond water circulation during the winter is in case there could be freezing damage to the pumps or plumbing, or enough ice could form that it diverts water out of the pond.
Water temperature is not an issue for either koi or goldfish.
If you can keep your pond running and your filters clean, do it.

.

 

[Lisak1]

Agree 100% with @MitchM . We run all winter (zone 5) and our fish do well year after year.

 

[sissy]

I would be very careful with your filter tank as those cans are not made as well as they used to be since plastic is recycled it is not as strong .Not sure where you live but I shut mine down .The tanks get ice on the top they get shut down and the small pump in a bucket gets turned on

 

[In2Caps]

I would be very careful with your filter tank as those cans are not made as well as they used to be since plastic is recycled it is not as strong .Not sure where you live but I shut mine down .The tanks get ice on the top they get shut down and the small pump in a bucket gets turned on

Thanks--it's a super heavy duty one--and I don't keep it outside or running during the winter. I rebuild it (with a new can) every two years. Just talking about whether to keep a small pump in the pond itself running for circulation.

 

[sissy]

I use a tuff tank and put plants in it .I put it inside a liner so it can run back into the pond in case it leaks .

 

[Meyer Jordan]

I would be very careful with your filter tank as those cans are not made as well as they used to be since plastic is recycled it is not as strong .

If extended periods of freezing or below freezing temperatures are expected, then all filters should be drained regardless of configuration or design.

 

[sissy]

Mine is not extended it can be for 1 day and then 1 day good and then 1 day bad ice ,on and off .So to me instead of risking the tank breaking or the water going over the top .With my luck the worst would happen Murphy's law .Our average temp here is 55 degrees but it can get down to 5 or 10 degrees and I get a lot of wind up on the hill and you never know if or when the sun will come out to melt the ice .I always play it safe .No real need to filter the water .I am sure people in climates like mine feel the you never knows also .I do keep a bucket in the pond with a small pump in it with lava rock filled dollar store bags and switch the pumps on and off from inside the house .I guess I may be little paranoid about things and especially my pond

 

[callingcolleen1]

I have run all my pumps and underwater filters since 1991. All my goldfish and oldest koi have been outside ever since.

I highly recommend you circulate your pond all winter, as the bigger koi get, the more oxygen they need. If you shut everything down the water quality drops and fish suffer. I recommend you use underwater pumps and filters if you expect extreme cold, as underwater filters do not freeze up like external filters.
It is more important to ensure water is clean and filtered and moving all winter. Koi and goldfish are just fine in ice cold running water so not to worry... I've kept mine outside in ice cold running water for decades and their all just fine and very healthy!

 

[mgmine]

I don't use a pump in the winter and the pond is frozen solid. Sounds like the same fish load that you have and they do just fine. I do have an air stone but in the dead of the winter it doesn't keep a hole cleared. It sounds like your ice is thin enough to just poke a stick through it every few days. I wouldn't waste the pump or the power to keep it going.

 

[Faebinder]

My pond is the same size. My waterfall filter/pump runs and my deep pump to bog continues to run. I don't get prolonged freezes though. Zone 6, min temp -1F in the winter.