Temperatures

[Zoodiver]

Then you have to keep it cool in summer... it's a huge ordeal keeping outdoor shark pools/ponds in control - ask Matt (Zoodiver) about the fun of it.

Keeping temps stable (warm or cold) outside sucks.

 

[Deano1956]

I don't know but what if you had a heated pool with a cover over the pool to block the sun. Like this.
http://images.google.com/imgres?img...4&prev=/images?q=pool+roofing&hl=en&sa=N&um=1
Also I am sure you would have to change a lot of the filtering and would need to put some way to sensor the cemicals

I'm sure you could pick up those nice pool covers for about $ 9.95 at your local hardware store.