What snail to introduce?

To all:

I am thinking about introducing some snails into my 1000 gallon pond to help eat uneaten food, etc.

Pond has only lillies.

I have read that the Japanese Trap Door Snail is easy to keep under control and is "the choice" for many pond owners.

Would like to hear what others think and their experiences?

Happy hobbying,
Vriesea

Hottest summer temperature mid eighties, coolest winter temperature low fourties.

Vriesea