Ponding in Spokane, WA

[Spokaneman]

I am a first time ponder. I built my 400 gal waterfall/pond about 6 years ago. As my first effort, it contains numerous design and engineering flaws. Nonetheless it continues to be home to a group of Koi and goldfish through several of our Spokane winters. My main interest in joining the forum is to find solutions to the various problems the arise due to the flaws mentioned above.

My current worry has to do with winter filtration. In past years, I have shut down my pump, filter, and waterfall. I have aerated the pond with a small auxiliary pump. Nonetheless, by springtime I have a thick layer of gunk on the bottom plus heavy algae throughout the pond. I'd like to operate a filter through the winter, but, with a submerged pump, I worry about my pipes freezing (as they carry water from out of the pond to an external biofilter and back) in sub-freezing temperature. If anyone has some suggestion, I'd appreciate hearing them. Thanks.

 

[DrDave]

Welcome to the Forum.
When you say freezing, how cold, and for how long under 32 degrees F?

 

[Spokaneman]

Our winter air temp can stay in the low to mid 20s (F) for several weeks. At times it can get even colder. Last winter the backflush/check valve (that keeps my bio filter from draining back into the pond) exploded from the ice in its chamber).

My current thought is to build a second biofilter closer to the pond and have the submerged pump push water up through the filter and back down into the pond, but not have it go over the waterfall. Instead it would circulate directly back into the pond. One concern about this is that I would have to turn down the flow of my 3000 gph pump by maybe 75%, and I worry about the strain this would put on the motor. Another concern about this plan is that I would be creating significant turbulence in the pond during a time when the fish are dormant (although that would probably work to prevent the surface from freezing).

 

[DrDave]

For a pond that small, can you tent it and try to create a greenhouse effect. If I was in your area, I would consider doing this.

 

[Spokaneman]

Well that would be a possibility were it not for the frequent Eastern Washintgon snowfalls sometimes measuring over 20 inches. The tent would have to be rather substantial.

 

[DrDave]

The Indians did just fine with tee pees. Unless you are challenged mechanically, that should be an easy build.

 

[Spokaneman]

When I discovered this forum I expected to gain information, not sarcasm. Guess I made a mistake. Wonder if this reply will get displayed.

 

[DrDave]

That was not intended to be a jab. A tee pee did not collapes under snow. That said, a lot of people are unable to grasp building something themselves.