Lily pad description

(Sorry, what is the problem? (non-english speaker))

"I can't see the bottom!" is what Wilson says when he examines a pond normally, saying how the water is very deep. While the phrase could correctly still apply to a lily pad, it doesn't make much sense in this context, it seems more like an oversight, re-using the same examination quote for the water on the lily pad. At least, that's my interpretation.