I would go with the heavier liner IMHO, as it is less prone to
puncture, but its a bit harder to work with. Used carpeting makes a
good base for the liner, just make sure there is no carpet tacks in
it. Usually you can get it free from places that do carpet
installations and sales. Gives it a good cushion. Then again vermin
and bugs may propagate around it, where roofing felt (tar paper)
would not attract as many insects, but lots of folks use old carpeting
for a subliner.

There are lots of places online that has good prices.....Even Home
Depots prices are cheaper than most local pond supply places here.

Here is an email address to a fellow that has some super great prices
on quality pond products and he will stand by his products and
company. His prices are great considering what a lot of places charge.

or
303-934-3200 monday-friday 8am to 5pm mountain time
Phone is the best way as he is kept pretty busy, and his shipping
time is short.

IIRC his 40 mil EDPM liner is about 29 cents a sq foot......his
Surepro pumps are eqaual to a Sequence and cost less, and he has all
the top brands of associated UV's, filters, skimmers, waterfalls,
submersible pumps and fittings like ball and knife valves..

Ask for Darron...He is a Horizon dealer, which is a major player in
the pond supply business. If there is a Horizon dealer in your state
he can not ship to you, but I think your state is ok, as it was not
listed as a state he can not ship to. Tellhim you seen his ads on
Koiphen.com which is another pond / koi forum.



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Put some color in your cheeks...garden naked!