Basement Exercise Pool Build

Hi all,
for the past couple of years I've been adding a basement level to our house. Part of the project is to create a small (but perfectly formed!) in ground exercise pool for my wife to use - although I suspect our kids are probably going to monopolise it...

Anyhow I've created a waterproof concrete shell for the pool - space is very tight because of where we could place the piling to support the excavation - we weren't originally planning a pool ;-).

I'm very keen to use an overflow channel to create a deck level pool but because of the waterproof concrete shell, the overflow channel will have to be inside the current perimeter and to maximise the pool width I need to keep the overflow channel to minimal width. I've found a product that seems to fit the bill (the A100 at www.aquabocci.co.uk) and was planning on using this with a lot of 75mm downpipes to a 110mm pipe running round the pool and to the expansion tank. This would also allow 100mm of insulation.

We can put a slight fall on the pool sides to encourage any water that overflows the drainage channel back into the channel. I've tried to do some calculations on pipe fall / diameter flow rates but wondered whether anyone had any experience of putting a 100mm drainage channel right next to the pool edge. Usually there seems to be a sizeable gap between water's edge and drain which I can't afford. I'm also trying to avoid using some form of bull nosed coping to prevent too much overspill as I want to tile the pool in large stone slabs and all of the bull nosed coping seems to be in commercial pool type finishes.

I'm not yet allowed to post any attachments of schematics or photos but the concrete shell dimensions are 2500mm x 4000mm (as I said, small but perfectly formed...

Any advice would be very much appreciated,
Thanks,
Rob