Maps of the Redondo area for the Battle of the Bays

[isghj]

What do you use as a source for reef/kelp/wrecks/boey location data? I mean in general for south california, not just redondo

Do you know of a brand of map I can buy, or a place I can download data from, that has high detail bottom composition? I want a map that can tell if I'm over mostly sand or rock, mixed, ect. I only found one in a store and it was zoomed way out to cover almost 20 square miles on a B size paper, that's too low detail to be useful.