I would guess the crappies are running from 6"-8" on average. I'd use a size 4-6 octopus/live bait hook and try some fatheads for bait... Fish the minnows as close to the cover you have in that pond. If you know how to use a slip float rig, I'd use one of those with 2-4 pound test. Use a small split shot so the bait sinks and start with the bait holding a foot off the bottom and gradually work the bait up until you start getting bites.