Skimmer box winterizing

waynefrcan

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Both my skimmer boxes have bottom cracks this spring. Was wondering what is the best method for winterizing them that you all have found. I overwintered the fish with water level at normal which means the skimmer boxes are frozen almost solid. Told this is what to do, but now I'm wondering if they should be sealed off and kept empty for the winter? Location is 5-6 months frozen. Manufacturer has no recommendations for either method listed in the manual or online.

Thanks
W.
 
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The cracks are caused just by the plastic itself being subjected to changes in temp. It's a lot of stress.

Skimmers can freeze solid and be fine because they're open. Virtually no one in the world believes this but it can be checked out by Googling info on why frozen pipes burst. The key is that ice itself doesn't expand, but it does take up more volume. To many people that sounds like the same thing, but it makes all the difference. Picture how the water in the skimmer freezes. It doesn't instantly freeze solid, right? It starts at the edges and moves in. As that ice forms it takes up more space.

In a closed system like a closed glass jar in a freezer or pipes in a house that extra volume causes pressure to increase in the system. More ice, more pressure. Eventually the glass, pipe or whatever can't take the pressure and it blows. In a house the blown pipe almost always happens far away from the ice, inside the house where the pipe/water is warm. If you look at pictures of blown copper pipe you'll see it looks like an explosion, which it is. A glass jar will explode, a can of soda will explode like a bomb. On the other hand an empty glass jar, no cap, placed in the freezer can crack. Many times it won't, but sometimes it will. The crack is caused of temp change, not ice.

In an open system like a skimmer the pressure can't build, so no problem.

The reason this is important is because I've seen many threads where people refuse to look up the info and choose to believe the myth. I have no idea why, but most of the time that's what they do. That leads them to do all kinds of strange things, mainly adding valves to seal off stuff. And there is an unlimited number of people ready to tell them their on the right track and make all kinds of suggestions to "try". Now they have a closed system and now they have real problems. Many people really, really hate learning stuff. It's boring, it isn't cool, whatever. But 30 minutes of reading can save you hours of work.

Then there's people doing stuff, the skimmer doesn't crack so therefore whatever they did saved the skimmer. It ignores the fact that skimmers don't always crack.

Stress crack in the bottom is common because picture the entire skimmer getting bigger when temp is higher, and shrinking when temps drop. Flexing back and forth. The bottom plastic is what is stretched and compressed the most. Just like bending steel back and forth will eventually crack so will plastic. Some plastics more than others.

The other way you can tell why freezing water didn't cause the damage is because of how much water expands when frozen. It's a lot. That would have cracked your skimmer in two.

So imo the problem is the plastic itself. Manufacturers have a choice in the type of plastic they choose to use. They have to sell products. If one product is a dollar less than another product most people will buy the cheaper. So if a manufacturer can save a little on plastic and the injection process/mold, they do. We force them to choose cheap because we do too. Plastic just doesn't hold up.

This cracking of skimmers also happens in warm climates. Out here in Phoenix people blame the sun or heat...but it isn't. It's kind of strange because I think most people consider plastic weak, cheap. But for some reason we also expect plastic things to last a long time. There's a reason manufacturers only guarantee these things for a year or less. They know how they're made.

I've seen people weld plastic skimmers back together, glue patches, goop it up. You can get a few more years out of it, maybe not. Replacing them is a more reliable, If you have to do that consider making your own skimmer out of EPDM. That flexes so can take temp changes no problem, doesn't become brittle at low temps. Save some cash and you can make the exact size skimmer you want which to me is gold. Here's my DIY for building your own.
 

waynefrcan

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Thanks, so how do they hold up empty for the winter? I have the biofalls empty and no problems so far but have not tested them yet this spring. THe plastic is polyethelene I'm told, but that's not from the company.

W
 
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There would be no difference empty or with ice. It's the temp change, some plastics being more brittle at cold temps and the design of the unit, some one steps on it when brittle, soil shifts... I assume if every one of them failed in the first year the company would have to change something. So that would make me guesstimate maybe 1% or less failure rate? Also going by how often I see the same thing posted in forums.

If it were the ice the failure rate would be huge for hard plastic skimmers. Swimming pools, ponds.

Common swimming pool instructions are to lower the level of water below the skimmer. The ice expanding destroying everything within 10 miles belief is a very ingrained belief by virtually everyone. So unfortunately, people want to hear that. For example, if you hired me to come out to fix your skimmer I sure wouldn't tell you want I typed in the post. One, it would take too much time. Two, you sure as heck wouldn't want to hear it, you'd think I was a moron and never hire me again. A lot of stuff is like that. But I get paid nothing for posting, so I write what I please. But like I said, it can be researched and confirmed if you like.

The weird thing about pools is have you lower the water and then you cover the pool. Rains come and water collects on the cover which pushes down into the water in the pool, which raises the water level back into the skimmer which freezes. Kind of funny really.

I grew up in Upstate NY, ground would freeze to 4'. We never lowered the water level in our pool and the entire skimmer pipe was only about 2' below grade and full of water. So it froze solid. Didn't crack. Now, if we had valve by the pump and closed that and also put a plug in the skimmer like many people suggest, we'd have a closed system and most likely would crack that pipe in a big way.

Some people say to blow out all the lines and then plug them. That's a lot of work, equipment. And for your trouble you end up with a closed system. No water, just air, so no danger right? Well, air expands and contracts. Air pressure changes as storms come and go. That closed empty pipe goes thru more stress than open system full of water. Maybe not enough to crack a pipe, but work a poor glue joint loose, you betcha.

Looking at the number of pools in cold climates, and that almost no one blows out lines, yet these thousands (maybe millions) of other pool don't have a major problem should be an indicator. If ice could burst open systems pretty much every single pool would be damaged every winter. Just doesn't happen. Yes, plenty of cracked plastic. It's plastic.
 

addy1

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I stuff mine with bubble wrapped in a plastic, displace most of the water, so far it has survived winters External skimmer.
 

waynefrcan

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Hi addy1, please explain in more detail how you do that, thanks much.

W
 

waynefrcan

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Waterbug, thanks for the info, we haven't always agreed in the past, but you have to be one of the best knowledge wise for ponding.

As soon as I find out what material these are made of I'll take steps to protect them. To make a skimmer sounds like a nightmare as I have alrdy the skimmer/liner cut out with no extra liner. More seams to make yuk!
 
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I guess one person's nightmare is another person's joy. I kind of hate to say to people "oh. it's easy" because it's very subjective.

World wouldn't be very interesting if everyone agreed. Personally I wish there were a pond forum that didn't have the poster's id at all, that posts could just stand on their own merit. Maybe that would allow actual discussion and learning. But probably very little interest in that. Actually, now that I think about it, I guess that's what a wiki is. The discussion takes place behind the scenes and it is a much more civil, serious discussion than you see in public forums. Those forums require people to post links that back their claims. Hmmmm, I need to check that out. I recently got a "reward" for getting 1000 likes, really makes me feel like I'm a kindergartener getting stickers so it was kind of a kick in the pants to try and find a more adult outlet for my pond addiction.

Good luck with the skimmer. I see you tried to get an update from a guy in another forum that has more serious discussion. I hope they do update. I forget what kind of skimmer they had, but in another forum (I don't know if we're allowed to mention other forums by name) a pond professional recently commented on Aquascape skimmers needing to be replaced every few years. I hate to pick on one company because I think it's an issue for all injected hard plastic products used outside, but it might be more common for that product.

Side note for Star Trek Voyager fans...The scenes about Project Pathfinder show some high tech gizmos that I think are made from skimmers. LOL. I haven't nailed down the brand....yet.
 

waynefrcan

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I just can't stand it when someone comes on for help and then disappears, no conclusion to the problem that we all can learn from.
 
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Well it is free...so we can't complain too much. But I sure would love more feedback. Seems like 95% of all threads where the person is asking for help there's no update. That's the main reason I post, to learn. No update, no learning. I can do a lot of experiments myself, but if we all pooled good data we could learn a ton.

But I'll say this, most cases where people are asked to update, and do, the result isn't good. They lost interest, the suggestions were more than 25 words and some of those words were long, or they did something that didn't work. When people do something and it turns out well they seem to have no problem updating. I think it has something to do with ego.

You can send the OP a PM. I don't track threads I post to, don't get emails telling me there's been a post. Too much of a time sink as it is. So I often get emails and PM asking me to respond to a thread. Maybe the OP just lost track. I never mind being asked, don't think they would mind a polite PM.
 

waynefrcan

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I also read one of your posts on another forum or maybe it's the same one you mentioned above. I liked the idea where you said to drill a hole by the crack and spray in the expanding foam to fill up any void. Question for you is if you put in to much you think that will bulge up the plastic and weaken it if it's a very big void?

I agree with your middle paragraph above and just to lazy to type all that in myself in post #9 lol. I don't exactly like typing a whole lot.
 

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Hi addy1, please explain in more detail how you do that, thanks much.

W
I take a white kitchen garbage bag, fill it with some bubble wrap, (you also need to stick a rock in the bag with the bubble wrap ow it floats) then I just shove it into the skimmer. It still has water in it all winter, but most of the water is displaced. The piping remains full, coming out of the bottom, the weir remains full. This was a -10 winter, the skimmer did fine. My only loss was one pipe the deer walked on, It must have been cold brittle, even saw the suckers hoof mark on the pipe. Going to cover it with some dirt.
 
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I have a Savio skimmer also with 16" weir. I take everything out of it and then fill it with pool noodles. Works great and real easy to do. I agree with waterbugs post. I will not even say it helps it to keep it from cracking but it can't hurt. I took them out of the skimmer to get everything going this year and there was about 8" of ice but the noodles pulled right out, so I feel it did work well.
 

waynefrcan

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I take a white kitchen garbage bag, fill it with some bubble wrap, (you also need to stick a rock in the bag with the bubble wrap ow it floats) then I just shove it into the skimmer. It still has water in it all winter, but most of the water is displaced. The piping remains full, coming out of the bottom, the weir remains full. This was a -10 winter, the skimmer did fine. My only loss was one pipe the deer walked on, It must have been cold brittle, even saw the suckers hoof mark on the pipe. Going to cover it with some dirt.
So the idea is less water to freeze = less possible damage to the plastic?
 

waynefrcan

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I have a Savio skimmer also with 16" weir. I take everything out of it and then fill it with pool noodles. Works great and real easy to do. I agree with waterbugs post. I will not even say it helps it to keep it from cracking but it can't hurt. I took them out of the skimmer to get everything going this year and there was about 8" of ice but the noodles pulled right out, so I feel it did work well.
I need a photo of a pool noodle lol
 

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