I've never had crab, lobster, or crayfish but I've heard that they will try to get a hold of your fish. The fish are usually quick enough, but you never know. Have you looked into shrimp (e.g. ghost, cherry, etc.)? :D
I keep to pools and ankle deep wading. :lol:
I've heard of people using them with livebearers, but I don't have any experience myself. I don't know for sure. :unsure:
It's on Discovery. They are supposed to have new shows this year that premier at 9pm EST. They had Les Stroud on last night. He jumped into the water from a helicopter and landed on a couple sharks. :blink: That’s one crazy dude, but I enjoy watching him. :lol:
I'd have to agree with OldMan47 and DaveyG...overstocking can certainly lead to aggression. Do you have a smaller, say 10 gallon, tank that you can use for fry? The crowding is going to get worse with each batch of fry.
Just something to keep in mind...that's all. Keep an extra close eye on your water quality when you add them for any changes. Let us know what happens. ^_^