I have 30 acres and was thinking about building a lake, what is a good length to get a decent run in?

You'll want at least 2000' in length, I believe that's typical for a ski lake. Minimum 225-275' in width. I'd go longer if possible.

2000'-2500' long x 275-300' wide. Hope your 30 acres is long and skinny. We are on a lake that is 1700' long right now and it is basically 2 tricks and turn around. Pain in the butt.

For a wakeboard boat loaded down, 2000' minimum, our lakes are 2100' and on average 5 wake to wake inverts or 4 out into the flats. If you'd like more info, feel free to contact me. I've built two man-made lakes