Liquid waterproofing/pond liner?
- Thread starter awrxynz
- Start date
bad prep the paint can fail as soon as you fill it with water.
pond liner lasts 20+yrs outside, inside your fish will all be dead before it leaks.
Pond liner you have to fold the corners to make it "neat"
Pond liner is cheaper.
pond liner lasts 20+yrs outside, inside your fish will all be dead before it leaks.
Pond liner you have to fold the corners to make it "neat"
Pond liner is cheaper.
All depends on your wooden frame work. Pondliner allows for flexing/bowing and you can use this to your advantage when you think about construction. Epoxypaint and fiberglass allows for no bowing and will cause the seals to crack at the seams if it does bow. I am biased because i have a 650gal pondliner with window running rite now lol, but i am also a fabricator so i understand fiberglass/epoxy. Both sytles of building can be equally as good when done correctly. Pros of fiberglass/epoxy is that we know 100% silicone will stick to it very well so there are no worries about your window adhesion (also simply these tanks have been around for 50yrs in the hobby). Cons of pondliner is its hard to find how to seal a window and expensive for the right product. I used Hutton Products GoldLabel Aquarium and Pond Sealer to attach my liner to acrylic with no problems but i paid $420 for a case of 12 tubes. I'd say thats pretty comparable to any fiberglass and epoxy paint you'd need for your build let alone the price of a pondliner on top of that. I search daily for another alternative as i am building another tank myself in the same fashion. It seems every person who builds a pondliner with window tank uses a different method and i cant say who's is best. Personally i dont think any silicone is needed at all with a 45mil liner and bolted acrylic but i havent finished testing yet. There has to be a rubber gasket that will work.
Wow great info! Thanks. I looked at Home Depot for pond lining, and th price is around $70 for a 7x10 sheet, but when I called a local pond store they would charge me $180 for the same cut out. Does this mean that homedepots liners are a lesser quality?
-Thanks
-Thanks
Check the thickness (rated in "mil, or thousandths of an inch) and material, if they are the same it should be comparable.
home depot liner is PVC and are NOT what you want...junk imo. If you go with a liner look for EPDM 40mil or thicker i believe i used 45mil Firestone EPDM. there is a huge difference in quality.
normal pool liners are 20-30mil...45 mil EPDM is good stuff and is most def. what they have at the pond store you called.
Awesom dude. Thanks. Ill ask if it is EPDM and the thickness. Next question would be.... What do I use to adhere it to the tank, the method (so I can still attach my glass "viewing window" ), and which silicone should I use to attach glass to front frame.
I know the info is someone on the net, but in bits and pieces. Id rather ask people with "experience" than to spend multiple hrs trying to find a thread that tells me all that I ask.
-Thanks!
I know the info is someone on the net, but in bits and pieces. Id rather ask people with "experience" than to spend multiple hrs trying to find a thread that tells me all that I ask.
-Thanks!
www.pondliner.com i think is where I get my liners. When I built my 330 with pond liner I had twin acrylic 3/4" windows I used 3m's 5200 sealed it around the windows and bolted the window to the frame. Never leaked a drop. I have a FRP tank right now and I used PL roof and flashing sealant.
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FRP tank I used the PL to seal the corners
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When I first tested out the 5200/acrylic on a plywood 180
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5200 again when I had the 330 in the making
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honestly from using both the PL and 5200, both which I put 100% faith into and both 100% fish safe, I like the PL better. smells like chocolate, real sticky and doesnt run on verticle surfaces like you see the 5200 does. The PL isnt $$ either. The FRP tank I built is a 7'x3'x2' tank and I used 4 or 4.5 tubes of the PL, so 20-25$ worth.
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FRP tank I used the PL to seal the corners
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When I first tested out the 5200/acrylic on a plywood 180
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5200 again when I had the 330 in the making
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honestly from using both the PL and 5200, both which I put 100% faith into and both 100% fish safe, I like the PL better. smells like chocolate, real sticky and doesnt run on verticle surfaces like you see the 5200 does. The PL isnt $$ either. The FRP tank I built is a 7'x3'x2' tank and I used 4 or 4.5 tubes of the PL, so 20-25$ worth.
To address a couple of quick misconceptions about epoxy resin (note, not epoxy paint) I'd like to quickly say that 1) it is not more expensive than pond liner and 2) it is flexible enough for plywood aquarium use. Epoxy resin is routinely used in industrial applications where flexibility is required.
But with that said, I do think pond liner is a valid consideration.
I know window attachment is a concern but I think there are enough long term liner tanks with windows to not worry about this too much.
Yes, pond liner is more flexible but epoxy is more than flexible enough.
A pond liner tank would allow for a modular design that could be moved. This is really only a concern at sizes that won't fit through doorways, around corners, down steps, etc.
Assuming the EPDM tape is as good as people report, liner tanks would be repairable and the floppy corners could be sealed up to prevent waste build up. An epoxy tank would be more infinitely repairable but unless one is really beating on a liner tank I think this is trivial.
As far as cost, epoxy can waterproof plywood at less than 30 cents a square foot. 45 mil EPDM Pond liner is around 70 cents a square foot and there is waste. In a two foot tall tank there would be at least 16 square feet lost to corners plus more lost to overlapping the top. There is the window cutout as well but at least you could use that for something. Not as useful as leftover epoxy, IMO.
A common tank size mentioned here on MFK is 8 x 4 x 2. Looking at Pondliner.com you'd need a 150 square foot liner for a tank that size.
But there is only 32 square feet for the bottom and and another 32 square feet for the back and sides. Window and top framing maybe another 15 square feet.
So in just that example you need almost twice the square feet of liner as you would epoxy. So even if you double up the epoxy and add fiberglass you're still only "using" about half the square footage that the liner would cover.
In reality most epoxy builds do and should use fiberglass resin. And most go thicker than the recommended 10 mils. So the cost does go up. Still, I think one could build a very strong, fiberglass reinforced plywood tank for the same cost as a liner sealed tank.
But with that said, I do think pond liner is a valid consideration.
I know window attachment is a concern but I think there are enough long term liner tanks with windows to not worry about this too much.
Yes, pond liner is more flexible but epoxy is more than flexible enough.
A pond liner tank would allow for a modular design that could be moved. This is really only a concern at sizes that won't fit through doorways, around corners, down steps, etc.
Assuming the EPDM tape is as good as people report, liner tanks would be repairable and the floppy corners could be sealed up to prevent waste build up. An epoxy tank would be more infinitely repairable but unless one is really beating on a liner tank I think this is trivial.
As far as cost, epoxy can waterproof plywood at less than 30 cents a square foot. 45 mil EPDM Pond liner is around 70 cents a square foot and there is waste. In a two foot tall tank there would be at least 16 square feet lost to corners plus more lost to overlapping the top. There is the window cutout as well but at least you could use that for something. Not as useful as leftover epoxy, IMO.
A common tank size mentioned here on MFK is 8 x 4 x 2. Looking at Pondliner.com you'd need a 150 square foot liner for a tank that size.
But there is only 32 square feet for the bottom and and another 32 square feet for the back and sides. Window and top framing maybe another 15 square feet.
So in just that example you need almost twice the square feet of liner as you would epoxy. So even if you double up the epoxy and add fiberglass you're still only "using" about half the square footage that the liner would cover.
In reality most epoxy builds do and should use fiberglass resin. And most go thicker than the recommended 10 mils. So the cost does go up. Still, I think one could build a very strong, fiberglass reinforced plywood tank for the same cost as a liner sealed tank.