Squirtle
The first water type Pokemon that you can get is Totodile which is one of the starter Pokemon.
torchic, the fire Pokemon mudkip, the water Pokemon treecko, the grass Pokemon
use water Pokemon and train it's in the first city town whatever use water Pokemon and train it's in the first city town whatever
its suicune, the water type dog
water or grass type Pokemon
I think there is a poliwhirl somewhere near there.
wingull is a water/flying Pokemon and you can get them at the start of the game in the first areas you can catch Pokemon in.
To go under water in Pokemon ruby, you must first have i think it is 6 or 7 badges and then have a water Pokemon who can learn dive... then all you need is to get the hm dive, teach it to that water Pokemon and you're all set! hope i helped a little bit =)
to get level 40 water Pokemon you first have to get a super Rod (from house on RT. 12) and get it by fishing. The Super Rod wil only get you level 40 Pokemon.
Victory Road Basement first floor on water.
I'm guessing squirtle
first time you see him all ground type i recomened water, and grass for water squrtule for grass ivusar he has ground type Pokemon every time you see hin