Swim and box crabs

Ooh, good fixes! 👍
Feel free to keep me updated with newer versions of this, if you want. I'm happy to offer more feedback, playtesting, etc., so don't ever worry that I'll be bothered if you keep sending me this. I won't mind! 😉

What you do is...
Place the Trigger Zone in the water, making sure the dimensions of the zone match the dimensions of the water...
Wire the zone's 'detected' output to the relevant logic...
And set the Trigger Zone to 'Detect Camera.'

If you programmed it this way because it was simpler for you in some way, then I totally understand and we need not linger on the subject -- I know that programming context-based actions can be difficult, and what you've done with this is impressive!