Aenon is an unknown location.  One suggestion is 7 miles south of Beisan where there are 7 springs within a radius of a quarter of a mile.  Another is 3 miles to the east of Shechem in Samaria where there is a place called Salim near a village named ‘Aimen, but there is no water there.

“much water” is literally “many waters.”  Enough water to even baptize by immersion in the summer.

John didn’t stay at the same location at the Jordan baptizing, though Jesus had been baptized there. He went to a different place as the need warranted. A human tendency would have been to enshrine the location where Jesus was baptized and then do all baptizing there from then on. We need to be careful to not get locked into doing things the way that worked in the past, but be open to the changes God wants to do and to opportunities that present themselves in the present. Be wary of making traditions out of procedures that worked once or even several times before. God is a very creative God, and likes to do things differently than we may expect.