Yes, but their advice is usually about the same SPECIES of fish or at least a close relative. Your crayfish, as far as I can tell isn't listed and you may not be keeping it properly either. Giving out generic information can be be just as dangerous as lying. What's good for a goldfish might kill a cichlid for example.
I'd very much like to know the species of crayfish that don't need air. If a crayfish doesn't have a filter, aeration, or a way to get their head out of the water, they will die. If I'm wrong, please give me some species names.