PVC liner vs EPDM

[Bluerooster]

I constantly hear all this talk about PVC liner not lasting more than a month or two, and EPDM being the best since pants pockets. My first pond is a combo of PVC, and EPDM, What I have found is this: After however many years it's been, both seem to be holding up ok. I did notice that where the EPDM contacts wood, or masonry, it develops pinholes. Kinda like rot, or insect infestation. The PVC seems to avoid that, and has been holding up quite well. I'm sure that UV has an effect on both, but I have yet to see any adverse reaction on either one. I don't remember when I joined this forum, (my guess about 4 years ago) but the PVC was new then, and is still quite soft and supple, while the EPDM where it's exposed has started to develop some cracking. And where it contacts the earth, has shown some pinholes. All above water level mind you, so it's not really a problem (yet).

 

[Bluerooster]

Oh, and when properly done, EPDM can be successfully mated to PVC, in a stream bed. I doubt I would try it in the middle of a pond.

 

[poconojoe]

Idk..I had the opposite experience.
When I was a newbie about 12 years ago, I didn't know there was any difference in liners. Unfortunately this is the case with most newbies.

I bought my first liner at Lowe's Home Center. I don't remember the dimensions, but it was $98.
Anyway it didn't last but 4 months and sprung a major leak. There was a substantial tear on the bottom. When I pulled the liner out, there were parts that had become hard and brittle. I'm guessing from UV light, or maybe not?

Then I decided to enlarge the pond, so guess what I did?
You guessed it...
I bought two more of the same (explicative) liners and thought I would seam them together.

I got a seam kit with all the necessary parts. Cleaner, glue, seam tape, etc.
Did a very careful job. Cleaned it hospital clean. No wrinkles. I laid it in my driveway and seemed it there. Seam tape on top and bottom.
I'm very meticulous with most things I do, so I believe I did a good job.

A couple months later the seam let go, in the middle of winter. I was adding 300 gallons of water a week until it got warm enough to change the liner.

Then I learned about EPDM and that the liners I had used were PVC.

That's when I realized I used an EPDM seam kit on a PVC liner. No wonder it let go, two dissimilar materials.
So, either you're lucky or are a lot better at this than me by seaming PVC to EPDM. I don't know how you did that. Most likely a different method of seaming.


By the way, when I pulled that seemed liner out, it too was hard and brittle as the first one.

I don't mean to doubt you, but are you mixing them up by chance? EPDM is a thick rubber, very durable. I don't know how it would rot, as you describe. I CAN picture the PVC one doing that though.
Or maybe the PVC liner you have is much thicker than the ones that Lowe's sells?

 

[Jhn]

@poconojoe Wondering the same thing, if blue rooster is mixing them up. I have a epdm liner in my current pond that is over 10 years old and just exposed the one entire edge of the pond and seamed another liner to it the epdm is just as soft and flexible as the new one, even in spots where it was exposed a little bit.

I’ve had ponds for over 30 years and used both types of liners, did the pvc thing in the first pond it lasted a couple years then turned to crap, got hard and brittle where the edges where even though it was hidden under rock and developed holes in it seemingly out of nowhere. Never used the stuff again have stuck with epdm since then, and haven’t had any issues with it, being brittle or developing holes.

@Bluerooster Count yourself lucky if pvc lasted 4 years for you.

 

[GBBUDD]

I have epdm on the slides of my rv no water keeping it cool sitting in direct sunlight at times for a year or more and I do have some cracking of the epdm. The rv is wow 9 years old now so any rubber exposed to the sun could fail in that time frame. No biggie there not the roofing but more of a gasket to direct rain away.

 

[brokensword]

when I was first constructing my winter tent, all info pointed to NOT laying my agricultural plastic DIRECTLY on the pvc pipe used for the 'hoops'. PVC is not UV resistant to my knowledge and apparently, off gasses the chloride, hence will decay. Doesn't surprise me in the least to hear of pvc liners altering over time and exposure.

I haven't heard/seen any reports yet of ponds lasting long enough when using pvc as a liner, so until more report in, I'll stick to recommending HDRPE and EPDM. As many say; the liner is the most important part of a pond!

 

[GBBUDD]

Pvc pipe is seriously compromised from the sun. Ask anyone from a hot dry climate what there pvc pipe looks like after only a couple years. It looks like someone placed it in a toaster oven and gave it a nice golden brown. How ever a simple coat of paint can stop this from happening.

 

[Kurtkoinut]

My pond just hit 1 year old. I didnt do my homework when I started, so I have pvc liner. Its 22 mil, which I think is very thick. I did seam two of them together, and so far no issues. I've asked for trouble, even planting some items directly on the pvc liner in piles of sand and gravel. My hardy lilies love it. This is only the second spring, so I'll keep everyone posted on how my setup holds out over time.

 

[GBBUDD]

Post a couple pictures @Kurtkoinut

 

[Bluerooster]

Not mistaken in the least about the EPDM and PVC differences. I'll try to get a pic of the EPDM decay. To seam the two together I used NP1, and lapped the seam 6", much like one would do on a roof.

 

[Kurtkoinut]

Post a couple pictures @Kurtkoinut

Sorry I dont look often to see posts. Here's the newbies build. 22mil pvc liners. I have added the larger open area last fall, and yes I seemed liners to do so...no leaks yet.

Total around 3000 gallons. I have two 800gph pumps just for water movement, and a 2000gph pump powering my filter. My filter is a small pool full of lava rock and plants. Water is pumped in the bottom, and it dumps into my small creek section.

Like almost everyone that wants koi, I started with too many, so I'm going to expand my "bog" to help keep the water clear. Right now it's a little cloudy, but not terrible. I have fancy tails, shubunkins, and koi. I know I'm overcrowded, and working on finding a new home for some of these.

 

[GBBUDD]

Looks nice, add a few years to the plants and it will all blend in nicely

 

[poconojoe]

Sorry I dont look often to see posts. Here's the newbies build. 22mil pvc liners. I have added the larger open area last fall, and yes I seemed liners to do so...no leaks yet.

View attachment 138703

View attachment 138704View attachment 138705

View attachment 138706

Total around 3000 gallons. I have two 800gph pumps just for water movement, and a 2000gph pump powering my filter. My filter is a small pool full of lava rock and plants. Water is pumped in the bottom, and it dumps into my small creek section.

Like almost everyone that wants koi, I started with too many, so I'm going to expand my "bog" to help keep the water clear. Right now it's a little cloudy, but not terrible. I have fancy tails, shubunkins, and koi. I know I'm overcrowded, and working on finding a new home for some of these.

View attachment 138707

Nice job!
A lot of work!
The water will clear up.
And those are some nice looking fish!