Smhog,
Tilapia is the generic name of a
group of cichlids endemic to Africa. In Texas we can legally stock Mozambique Tilapia (Oreochromis Mossambicus).
A great read about them is at this link:
http://srac.tamu.edu/tmppdfs/9922301-283fs.pdf I haven't stocked them with CC or yellow perch, but have stocked them with a large variety of other warmwater fish without any problems whatsoever.
Yes, a constant well water flow will help with water clarity and reduce algae. Generally little nutrients in well water...but also low in DO. You may want to run it across some rock structure to help add oxygen to it before entering the pond.
However, even with constant well water, you may experience some algae. Try it out and see what develops. You may or may not need additional controls.
