mass outbreak
You actually find surskit in the grass not in water.
if you mean how can you get surskit in pearl? then migrate it from a GBA game and catch it in the pal park.
You aren't able to catch a surskit in Sapphire. You have to trade it from Emerald or elsewhere.
No you have to train surskit to level 22.
It may differ from other games, but I managed to catch a Surskit in Route 102, beside Oldale Town.
Wait until the TV in the game tells you there's an outbreak of surskit go to the route they mention to catch one. If your having a hard time get one from ruby, sapphire or xd gale of darkness.
You'll need to trade for it, because it isn't in the Pokemon Emerald. To catch it, you must mix records with Ruby or Sapphire.
In Pokemon pearl, the Lucas' little sister has to tell you where it is. She will tell you that its in Lake vVerity. Use surf, then go to the little island where the cave is. Don't go in there but go south west of that cave to where grass is. Go on that land and search until you find a surskit! Then catch one (most likely with a poke ball. Surskit is not a very strong Pokemon so it is very easy to catch)
You can find Surskit at route 102 and 114, however it is pretty rare because its catch rate is only 1%. You can also find it at route 117 when you hear there's a swarm of them on TV.
This Pokemon only appears if you watch TV in the game and it says there's a outbreak of surskit at some route go there to catch one.Like Skitty, it's very rare. However, you can capture it at route 102.
No Surskit's evolution is Masquerain.
Surskit evolves into Masquerain on level 22.