Welcome to PondBoss!

That sounds like a cool pond with many possibilities. I'm not much on stocking advise, but certainly check the year's temps out for the use of trout. As for LMB (large mouth bass), they are not typically real successful in a small pond (they tend to overpopulate, overeat the forage, and stunt). Think about CC (channel cat) for a food source. Like trout, they would probably be a put-and-take fish requiring yearly stockings to keep up the population. I did say "probably", I'll leave that discussion for those with the proper experience. HSB and HBG (hybrid striped bass and hybrid bluegill) are a good combination for small ponds as they do not reproduce at the rates of pure strains...HSB rarely breed in a pond, almost never, but running water is one of the requirements along with rocky banks. You may need some RES (redear sunfish) for snail control in necessary.

Fertilization would be a waste of money and effort UNLESS you can stop the inflow and the pond retains it's water level adequately. There's the real question...does the pond hold water without the inflow constantly running. You could put a valve in the inflow and only use it when the water level dips. 2" inflow does not sound like much and some fertilization might not be a waste, but it would be better to keep your fertilized water in the pond. Do you know how much water the in and outflow pipes are producing? A five gallon bucket and a timer would be a quick test to perform. Next question is...is the in and outflow a consistent flow rate year around?

Look into FHM's (Fathead minnows) and some spawning structure (pallets work well). With only a couple bass in there...a few pounds of minnows could start breeding and get out ahead of them given that the water conditions are conducive to there survival and spawning needs. They are not too picky, but too clean of water may not feed them well enough. I'll leave that concern to the experts as my pond is filthy compared to crystal clear waters and they love it.

Your pond sounds really cool, I envy your set-up.

Fish on!,
Noel