Great job you might want to add a 4 inch prefforated pipe to drain any water that sits inside the bottom key it is not always nessary but some times the sand will get a smell when swimmers kick up sand from built up nutrients that wash in and settle underneath the bed the pipe will drain it off


Scott Trava
Catskill Pond
http://catskillpond.com
scott@catskillpond.com
Returning Catskill Waters To A Simpler Time
EST. 1923