Hello,

OK I need some refresher information since by brain is frozen from this
cold snowy winter.

I forgot the material name of the liner used in extreme cold conditions.

I also recall there was a formula for calculating the size of the liner
depending on length, width and depth of your pond.

I want to make my pond deeper so I am just going to cut the bottom of
the existing liner so I can keep on digging and then just put the new
liner on top of the remaining old one. If anybody has a better way of
doing this then I would really appreciate the expert advice.

Thank you !