You ask "RES may act as predator ?" Do not worry about this for what you are planning to do. RES may eat a few minnow larvae but not enough to cause concern or measurable loss. Larger RES will feed on other larger invertebrate items than smaller sized BG.
You ask "If I feed Purina Gamechow (I can get locally for $17.50/50lb bag) to the 1-3" CNBG, should I expect them to spawn before next spring ?" For the fish and sizes you are stocking Only feed Gamechow if the fish you buy are ALREADY eating Game show which I highly doubt they are. Just about all of your RES regardless of size will not eat Gamechow pellets for you. Thus no game chow this year.
I doubt that you will get a very large percentage of 3" CNBG in the 1"-3" mix. If you do, you are darn lucky. Most will be 1"-2". They will not spawn even it TX until July or Aug 2008, - maybe if your very lucky, mid to late June. Larger RES (4"&5") are likely to spawn in June 2008.
"Since it was recommended to cut back to 500 CNBG instead of 750, would you still go with 20 lbs FHM ?" Yes and if you add LMB this fall add another 20-30 lbs FHM in spring 2008.
