I would like to stock LMB, CC, and FHM. I already have some BG and GSF. The spillway drains into a 6' by 6' pool that is about 6' deep. From there the water flows down a creek. So if I were to stock adult fish the only fish that would go through would be the fingerlings and fry right? Before we drained our pond, I was always able to take a fishing net and scoop out fish that went through.
I think it would depend on what size culvert you have, and what type of grate you choose to use, as to what size fish could escape.
In my opinion, the key is to not screen off the end of the pipe, rather screen off a bigger area AROUND the end of the pipe.
I think you will always lose some fry, but in your case, with the types of fish you listed, it shouldn't be a problem. Your LMB, BG, GSF?, and FHM will reproduce in your pond. The CC may, or may not. They never have in my ponds. The FHM may escape through the pipe, if they survive predation by your LMB.
What kinds of fish are present in the creek now?
