BUILDING A POND COVER!

When my friend Klaus comes to visit every year from Bavaria, we usually end up doing some kind of project together.
This September, 2016, it was building a cover for the pond, something I have been fantasizing about for several years.

It always seems to me that the fish have a very long and difficult winter and sometimes I lose some. Perhaps with a cover, I could reduce the snow load and shorten the cold season enough to make a difference to their winter ordeal.

I had looked into buying a prefab cover but none of the sizes would be a very good fit and the better ones were quite expensive. And only the high end ones would come with UV resistant clear plastic. Mostly they were quick assembly garages or shelters with opaque covers that would keep the fish in darkness all winter.

Then I was thinking about building a custom frame out of wood. Several challenges to that including how to cover the span of the pond with good support yet not too much weight and heavy lumber. Also how do you get out over the pond to work .. a project in itself.

I eventually contacted Clarke’s Koi Ponds in Scarborough who I have dealt with for years, and they had good suggestions and even a web site showing how they build a hoop cover. They do this often for their customers and in the end this seemed to be the best approach. It uses 1 1/4” PVC electrical conduit which comes in 10’ lengths which join together with a press fit to give you any length needed.

They even show how to reach the top of the structure over the pond, by using a ladder horizontally. This is light yet strong and a great idea.

Klaus and I agreed on this design after tossing around some other options, so I purchased most of the parts before he arrived. The special UV 6mil plastic is the only thing not easily available (comes from a factory in Vineland, ON) but Clarke’s keep a supply there where I got enough for the project.

The basic process is simple and surprisingly easy to execute.

Wherever you want a hoop, you hammer a 5’ length of 3/4” metal tubing 2.5' into the ground.
Then the 1 1/4" electrical conduit pipe slips over this and you can bend it to meet the matching tubing on the other side of the pond.

In this pic you can see the first hoop in place and the metal support pipes already hammered into the ground with a special pounder we rented from Rice’s Hardware in Meaford. The hoops are about 3’-4’ apart.

I only had one length of ladder so we borrowed another section from neighbour Jesse at Bunny’s house. It sags much more than the rigid section but it held our weight.

The first hoop and ladder bridge

Once we had all the hoops in place we had to secure them with a longitudinal pipe running the length of the cover. We used plastic ratchet ties, two to each joint.

Securing hoops together with longditudinal pipe and
      plastic ties.

In the end we added another horizontal stabilizer half way down which helped secure the whole structure.

Pond hoop horizontal stabilizer

The final step was to add the UV plastic cover which required 3 of us. Luckily it was big enough .. our measurements had been accurate (whew).
It comes in very wide roles, I think this piece was 30'x35'. It's expensive but if you use the regular plastic it disintegrates in the sunlight.

The building team

Inside the hoop cover.

Once the cover was installed it immediately created a cozy space inside. It seemed warmer from the greenhouse effect and the lack of wind.

Inside the hoop cover.

A few days later I added an entrance to make it easier to get inside.
I also picked up some sand bags and sand and used them to secure the plastic cover against the wind.

Pond cover entrance.

It’s been so warm out that I restarted the water pump after shutting it down when it went down to about 2C overnight some time ago. Now the water is back up to 60C and I’m still feeding the fish a bit ..   :)

Feeding the fish

It feels great  to hang out inside the dome with the fish. They seem to like it too.

Fish inside hoop cover.

It's very pleasant inside the dome .. hopefully it will survive the winter and the fish will have an easier season.

Inside the dome feeding the fish.