Empty The Skimmer?

[Anthony]

I live in zone 6a (-10 degrees) and have an Aquascape signature series skimmer.
My question is do I need to lower the pond lever below the skimmer opening and then drain the skimmer box to prevent it from cracking when it freezes, having to replace the skimmer would be a HUGE problem in my particular application so it would seem the thing to do.
The only thing making me question this is by lowering the pond level it would leave the top of the liner exposed all winter and wonder if that is that a problem?

 

[Waterbug]

I've never been successful in anyone ever believing this but I'll give it another shot...most people have heard of pipes bursting during a freeze, the confusion is this only applies to closed systems, like the pressurized water system in houses. When you look closer you will see that the burst points never happen anywhere close to the frozen part of the pipe. This is because it's water pressure that causes the burst not the ice. The ice causes the high water pressure.

Water expands about 9%. Clearly a skimmer could never take anywhere close the that kind of expansion, but skimmers normally make it thru the winter just fine. It's because it isn't a closed system, or shouldn't be, so water pressure can't build. You want the pipe on both ends to be open, any valve should be open.

However, skimmers are plastic. Plastic is more brittle when cold, pipes contract, frozen soil heaves, stuff happens. So skimmers can crack. But it's not water freezing inside the skimmer that is the issue. So you should be able to leave the water level at normal.

Also, if you're overwintering fish, and if this is a Aquascape design which are fairly shallow, lowering the water could have a negative impact on fish.

Exposing a PVC liner has issues. Exposing a EPDM liner is less of an issue, only UV damage. I wouldn't consider exposing EPDM to be any issue.

 

[crsublette]

Hmm, don't know. PVC can withstand an incredibly high psi, even more so with sch80, more than any pond pump could exert unless the pump has around 200+ foot of head height ability. Yeah, the expansion of ice that helps to create a closed system further pushing the water causing the high pressure is what cracks.

I bet its the ice expansion more than anything that causes cracks.

You could put a small milk carton in the skimmer. This will allow the ice expansion compress the carton. My skimmer is one place where I put my floatable heater at the wier door.

 

[Anthony]

Exposing a EPDM liner is less of an issue, only UV damage. I wouldn't consider exposing EPDM to be any issue.

Could you please clarify, is it less of an issue but still and issue because of possible UV damage, or it not an issue?

You could put a small milk carton in the skimmer. This will allow the ice expansion compress the carton.

What kind, plastic? how do you use it? Lid on? floating on surface or do you need to partially submerge it somehow?

 

[addy1]

I take a plastic bag, fill it with bubble wrap, stick a heavy rock in to give it some weight. Stuff it in the skimmer, it displaces most of the water, skimmer is fine for the winter.

 

[crsublette]

What kind, plastic? how do you use it? Lid on? floating on surface or do you need to partially submerge it somehow?

Nothing special. Just a regular old milk carton, something able to fit in your skimmer. Add somes rocks in it to weight it down so about a 1/4 or 1/2 of carton is underwater and glue the lid.

 

[Waterbug]

Could you please clarify, is it less of an issue but still and issue because of possible UV damage, or it not an issue?

EPDM is damaged by UV. Exposing it to more UV reduces its life. That's a negative. You asked if there's any problems with exposing liner. Whether you consider it a big enough problem to worry about has to be your call. I wouldn't worry about myself.

 

[Anthony]

Thanks addy, I like that idea. Now if I can only find some free bubble wrap.

Thank you all for your answers, they have been helpful.

 

[addy1]

I use bubble wrap because moisture won't bother it and it is easy to stuff in the skimmer. If you have styrofoam peanuts, styrofoam packaging anything will work.

We are still too warm to worry about it, all my plants are putting up new flower buds and flowers, crazy plants.

 

[Frankp]

I normally fill a two liter water bottle about half way and place that in my skimmer box. Keeps the ice from causing any damage.

 

[sissy]

You can fill a gallon milk jug with crushed oyster shells as they won't freeze