it depends on the Pokemon that are evolving
Chat with our AI personalities
lv28
In Pokemon Battle Arena, Pokemon only compete in battles and contests. However, they do not gain EXP or level up.
You have to go to vermillion city and search for a house in the left inside the house is a fisherman talk to him and he will give you the old rod then you can go fishing well only to capture magikarps. If you want another water type pokemon go to petalburg and then go to the beach and go to the bushes near the beach then you will find a wingull. You can also give your water pokem the TM water pulse by beating the water gym leader Misty. But I forgot which city was that but I know it is near Vermillion City. You can even teach water pulse to a munchlax where you find in the S.S Ane in one of the rubbish bins. And one more thing when the Magikarp turns to level 20 it will evolve to a Gyrados!
You cannot catch it in the wild. You'll need to:Trade for itTransfer it into the Poke Transfer Lab.
go to the big brown building and talk to the bald guy sat at the table on the ground floor after talking to him the museum is no longer blocked by team aqua/magma, go to the top floor and he is the scientist