[pbnj]

Hello all, we are enlarging our fish pond with a new larger liner, and have some questions. There is an existing hard-sided plastic pre-formed liner already in place, but we want to make it longer; should we leave the old pond form, cut away the end, and extend it with our vinyl liner, or remove the old one entirely? Also, the liner (black, smells like a new swimming-pool liner so I suppose it's vinyl) had a standing seam down the middle; does the folded part of the seam go underneath, or in the pond? I mean, the liner is darker and shinier black on the side that the seam stands up on - I would think that the darker side, which looks more waterproof, would be against the pond water, but the seam stands up on that side, and I would also think that should be underneath, so as to be hidden - but they can't both be right! If we do leave the old rigid pond form in place, and extend away, can we assume that we can cut away the end down to the ledge, and drape the liner into the old pond form (with another smaller liner bridging from the seam where the new liner meets the form, to the other end) - OR must the liner be all one piece for the whole pond? Sorry if these questions are not worded clearly - I'm gesturing in the air, but can't get the computer to see that. The fish have already been moved to their temporary place (the upper pond where the waterfall comes from - and yes, they have been gated away from the waterfall outlet) - so Help!

[Stonehenge]

I have a question for you to ponder (no pun intended) - if one side of the pond liner was truly more waterproof than the other, would it matter?

Some liners are made with a picture of fish painted on one side, and for some reason we feel compelled to install those liners picture side up. But the others show no directional install instructions, so we just install it whichever way it happens to fall. It's my suspicion that the look of the seam has more to do with how it's seamed than whether it is more waterproof or not.

As for marrying old, plastic prefab liner to new, EPDM rubber liner (I'm assuming that's what you have?) - don't do it. You may not get a good seal with seam tape, the two materials will likely expand and contract at different rates, creating opportunities for small gaps to form.

Just put the old one at the end of your driveway with a free sign on it.

[Malrex]

Agree with Stonehenge. Take out the preformed, and use 1 piece of flexible liner for the size you want, side doesn't matter.

[pbnj]

Thanks so much - we have reconfigured the pond to fit the liner we have, and the husband is sweating outside at the moment with the installation. Wish us luck!