Question
Our water feature is made out of big stones in a semi-circle shape--two tiers--setting on concrete patio up against a  brick wall.  We have lined both tiers with thick pond liner that was mortared in each tier.  The bottom tier is 16 inches wide, 15 inches deep, and 9 feet long in a quarter circle.  We cannot keep water in the bottom tier of this water feature.  I have been looking for a more stable insert in the bottom tier in a quarter cirle that we could put down in the bottom tier to hold the water since the liner is not working.  Do you have any ideas to fix the problem.  It is sitting on a concrete patio made out of large stones with the lining attached inside by mortar between the stones.

Answer
Dear Nina,

Thank you for you e-mail.
However the answer is not so easy.
It totally depends on the construction.
If you sent pictures it might be more easy.
Also a possibility is when the feature is not big and temperatures are high and / or much wind there could be some water vaporizes.

Hope to hear from you soon.
Kind regards,
Raf