I asked for two reasons, the first is that some Vals such as the Jungle Vals are very tall and grow very fast, probably too tall for your tank. While other species vary in height.
The other reason I asked is that I also want to know more about the short ones while I think you would want medium heights.
The one thing I do know is that they are tough, easy to grow and some Vals have Twisted versions that look sensational.
Now we wait for the experts and thankfully this forum has a lot of them.