Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.
Benefits of registering include
In my limited experience, pre-dive food is good. Doesn't really matter as long as there's a lot of it. I caveat this by saying don't eat rye bread before a boat dive if you get seasick. I've never been seasick in my life until my recent trip to Hawaii and rye bread is pretty damned harsh coming back up. So, anything as long as it isn't rye bread and there's a lot of it.
Between dives, anything as long as there's a lot of it. Prefer light foods though.
Post dive, anything, as long as there's a lot of it, and booze... that's a nice addition.
Specifically, fruits, pastas, yogurt, bagels, burgers, etc. Stuff that's easy to pack/prepare.