Here's a photo of a green plant that I cannot ID. Hopefully I'll find out what it is. The pet shop owner didn't know what it was.
Since first posting this, the plant is a Pennywort. This plant can be either rooted in the substrate or used as a floating plant My fish guru, as I call her, says this plant, as a floating plant would be great in the betta tank. So, I guess that's where it will go. My thanks to Dawn Moneyhan, my fish guru, for all the help she has given me. It's not a plant that is easy to grow.