Packery is about 14' deep at most. Fairly short where the fish are. Maybe 200 yards max. I used to see alot of snapper and snook. When the reds are running you'll see black drum in there as well. I wouldn't really scuba it at 14' you really don't need tanks. Vis can be a problem with ANY surf it's pretty much undiveable. You'll fight off a few fisherman most of the time.
I was in Corpus on Business on Thursday-Friday. Decided to hit the Packery Jetty on Thursday evening.
There were 3 or 4 Divers spearfishing in the Channel side. Don't know if they got anything. They did report tons of Snook stacked on the edges of the Channel.
Others were catching Slot and Oversized Reds on the Northe Jetty Surf side on cut bait.
I threw Kelly Wigglers and a Lipless Crank Bait and caught small Jackfish and a few keeper Trout. The 2 lb Jacks fought as hard as any Trout I have ever caught.
Anyway, nice set up there. will do it again when I'm there next time.
Drive North 20-30 minutes to the Port Aransas Jetties. It is a much deeper and wider channel that is more safe to dive. Look up the tide charts online and go during the high tide. there will be lots of sheepshead, trigger, snapper, snook, and you can sometimes see some snapper or jacks. the oil rigs in the area are a good place for some diving and spearfishing as well