Bobbss, unless aerating the pond, water 6 feet deep or more will be toxic in the summers here, but you want at least 30% of the pond at an 8 foot depth for our typical winters for fish to survive well in. With a 7 acre "steep" watershed, you might sustain one acre, but 3/4 acre is more likely.

BTW, it's nice to have another new Missourian amongst us!