On Route 230 in Pokemon Brilliant Diamond and Shining Pearl (BDSP), there are two locations where you can find Water Stones. These stones are valuable evolution items that can be used to evolve certain Water-type Pokemon. I’ll provide a detailed answer below on where you can find them.
1. Located at the easternmost shallow water at the southern part of Route 213, north of Swimmers Evan and Mary (requires Surf TM95):
To find the first Water Stone, you will need to head to Route 213. Once you reach the southern part of the route, you’ll notice a shallow water area. You will need to use the Surf TM95 move to navigate through the water. Go to the easternmost part of the shallow water, and there you will find the Water Stone. It will be sitting on the ground, and you can simply pick it up.
2. West of the Rare Candy (requires Surf TM95 and Rock Smash TM100) (Hidden):
For the second Water Stone, you will need to go to Route 230. This route is accessible after you obtain the National Dex and defeat the Elite Four. Once you reach Route 230, make your way to the west side. Keep an eye out for a Rare Candy item on the ground. The Water Stone is hidden in the same area, but you will need to use Surf TM95 to access it. After surfing to the west of the Rare Candy, you’ll find a rock blocking your way. Use the Rock Smash TM100 to break the rock and reveal the hidden Water Stone.
It’s worth noting that the Water Stone can be used to evolve various Water-type Pokemon, such as Poliwhirl, Shellder, Staryu, Eevee (to get Vaporeon), and Lombre. Make sure to use it wisely on a Pokemon you want to evolve!
I hope this detailed answer helps you in finding the Water Stones on Route 230 in Pokemon BDSP!