Take the experts advice over mine but since I got here first will give you my opinion.
Unless the RES are feed trained, I don't think it would do much good to feed them. RES are persnickety on what they eat and fish pellets are not much on their perferred eating list unless they have learned to eat them. They like to eat off the bottom, not the top of the water so it is also hard to monitor if they are eating the pellets or not after they eventually sink.
You were talking about 700-1000 fish in your original post. With 10 acres I don't think you can do too many for that size lake. The question is how many is too many for that small area you are putting them into. I think you could put lots if you are only going to use the blocking area to aclimate them for a day or two. However if you are planning on putting some size on them and keeping them there for a while then how many can effectively be fed becomes the issue.
Here is what I would do, right or wrong. Like I say, if the experts say different, do as they say and not as I say.
I would get 1000, put them in the blocking area for several days to acclimate them to their new water. Then I would figure some way to let some out. Not sure how the best way to do that would be, but try to let a third to half out. Then put the net back across and let it go a couple weeks. Try to sample them and see how they are doing and maybe let some more out. Then leave the blocking net up as long as possible while trying to monitor and see how they are doing.
I guess my point is, let some out at different times to hedge your bets and hope some make it. If you could raise some within the net that would be great but that is going to depend on where you live and how cold it gets. No use trying to leave them in shallow water in the winter if they will freeze out. But if you are where they could survive in your cove maybe even try to grow some to several inches within the pen. Thing of it is, can not grow many in that area because of food limitations.
That is what I would try.
