How do you get shoal shells in Pokemon Ruby?

Answer 1

In the Shoal Cave, you may come across two exclusive items - the Shoal Salt and the Shoal Shell. There are about four of each at any given time in the cave and together can be traded for a Shoal Bell. The problem is: how do we get the other when we already have one? The is simple: we must visit the cave at the right time.

Shoal Cave operates on a timetable. At a certain time each day, the tide in the cave changes from high to low and back again. What this means is that when there is a tide in the cave, a certain section of it is cut of and cannot be accessed until the other tide is in. If it is high tide, then you will find that the cave is filled with water and places high up in the cave are assessible. However, it blocks off the lower entry points to the other parts of the cave. It is only when low tide has come that you can access these areas - but then you can't get high up anymore.

Between 9am and 3pm (according to the in-game clock), the cave is in high tide. This is when, if memory serves me correctly, we can gather Shoal Shells. It also reaches high tide between 9pm and 3am.

From 3am to 9am, the cave is in low tide. This is when the other 'Shoal' can be found - the Shoal Salt. Note that low tide is also between 3pm and 9pm.

This tide timetable' applies to both Ruby and Sapphire (and possibly Emerald).