First noticed by Moses...
It may not have been native to Egypt, which would explain how Moses would have been “surprised” to see such a miracle. Anyway, God used the ordinary in extraordinary ways to get people’s attention. Water from a rock, quails by the buckets (the birds migrate across the desert and some have to stop or fall to the ground from exhaustion); but the parting of the waters defie explanation. That is the defining moment for the Children of Israel. BTW, did you see where they have found the Egyptian chariots in the Red Sea?