The pond is not too deep, you can walk to it!
Maybe a bug then? I was trying to along the coast but it wouldn't let me go beyond the shore. I might try it again. Also wasn't sure how many lights there were to catch so I was never sure if I finished it.
It's 5 lights in total! For the beach one, there is a few rocks that go in the water you can walk on.
Oh, awesome, that's the only one I missed then.