I'm curious—what would your ideal scuba diving pool look like?
I hope this doesn't derail the OP's thread.
Off the top of my head....
I'd like it to be dimensioned to suit standards. It would have to be a minimum of 25 metres long, 12.5 meters broad with a maximum depth of about 6 metres, a minimum depth of about 120-150cm. The shallowest part should be controllable with an adjustable bottom so that the minimum depth can be adjustable to suit average lengths of students from 10 years old and up (regardless of the discussion of whether or not kids that age should be trained). About 1/2 of the pool should deepen in 1 metre terraces down from minimum depth to about 3 metres and then slope sharply down to a trench at 6 meters.
There should be anchors on the bottom that can be used to attach things like buoyancy diamonds and buoys at about 2 metres, 3 metres, 6 metres. Two anchors (left and right from the middle) should be installed at each of those depths.
Along the sides of the pool there should be some way for students to hang or stand on the side of the pool (there are moments.... there are moments) and the edge of the pool on the deepest part should be about 1 metre above the water level. Along the entire back of the pool a highly reflective mirror should be installed so the divers can see themselves. Ladders with broad steps on both ends and both sides.
That's just a quick sketch of what I would personally find useful. I'm sure if I thought about it more I would want to add to that.
R..