Need advises on building an above ground pond

[specialone0812]

I am planning to build me an above ground wooden pond.
This pond will be 6'long x 4' wide x 30" tall and will sit next to my deck under my partial covered patio, so I prefer it having a wooden look. This pond will be a house for some small koi fish and some plants: water lilies, lotus ( i do not know where to buy them yet)
Here are my planned materials:
Frame with treated 2x4.
Cover inside with 1" plywood.
Liner underlay
Water liner
Cedar exterior
Above pond filter - similar to bog filter with gravel and plants.

I saw some water liners at Lowes and Home Depot, but did not know if they were good enough.
If someone have tried this Make-It-Yourself pond, please share your experiences/problems/difficulties.

I like these two ponds:
pond.jpgpond 2.jpg

[BrAin]

Saw a post where a guy bought a billboard tarp and used it as a liner. They sell them on craigslist

[specialone0812]

I guess that material will get crunchy and can crack under cold weather and UV light.
So far, I have found this good liner at the best price : http://www.webbsonline.com/Category/Pond-Liner-Underlay
10x15 for $83

[BrAin]

Cant beat a 20 yr warranty. Those are way better than the billboard.

[kaleido]

best affordable liner is permalon by reff industries. They will cut it to size and even make seems so you can get a perfect fit. BTW if you want all that stuff you will want a larger pond. http://www.reefindustries.com/permalon.php link to my above ground pond https://www.flickr.com/photos/koiboy...57603136842383