Mike367, hey that's an easy one that I can answer. POT means Profit On Turnover. eg. say after a given length of time you have made bets of say $10,000 and are showing $1000 profit, then you have a POT of 10% (most pros so I'm told would be happy with something like that) personally I would LOVE 10% POT, I haven't achieved it long term (yet)

PS. I think your plan to have any chance you would have to bet at least Best Tote+ SP, or at least Top Fluctuation (both readily available)

A couple of filters that you may want to consider is
(a) must have a win in exposed form i.e. last 4 runs (this time in)
(b) a win % of at least 25%

also look closely at restricting the distances (this is a personal preference) say 1200m to 1999m

Good luck!