It has built-in ledges for plants to sit on and is made in the UK. View Deal ... can use the flexible liner option. No matter what garden theme you have, your small pond should complement it.
This will help protect the butyl liner being punctured. A layer of pond underlay or old carpet above the sand will provide additional protection. Get a friend to assist in unfolding the butyl liner.
If the water level in a lined pond drops or the flow of water decreases, check that no part of the liner has slipped below the water level. If a pond is leaking, it needs to be drained and inspected.