Water Temple: missing a small key?

A red rupee is the correct reward. In the Switch 2 remake, the chest beneath the Water Temple’s central pillar contains a red rupee. There’s also a Gold Skulltula on the wall. If you opened this chest expecting the Small Key from the older game, head back to the main chamber. Your next key depends on which hook you’re carrying.

Find your next Small Key

I have the Hookshot and just opened the rupee chest

Return to the room where you raised the water inside the pillar. Take its 2F exit into the hub. With the water halfway up, go east and bomb the cracked wall. Follow the flooded passage past the Stingers to a room with a water jet and a switch.

Hit the switch to lower the platform, stand on it, then hit the switch again. Ride up and take the passage to the Small Key chest. Back in the hub, the locked door on the west side of 2F leads toward the next water-level crest.

I have the Hookshot, but that east-side chest is already open

Check the two low-water rooms. Lower the water at the crest above the shaft where you met Ruto. At the bottom of that shaft, light the unlit torches and defeat the enemies beyond the door. The other key is in the whirlpool room: use the Iron Boots to reach the dragon statue, Hookshot the switch in its mouth, and take off the boots to swim through the gate. Surface beyond it to reach the chest.

I already have the Longshot

Set the water to its middle height. From the hub’s second floor, find the eye switch on the north side. Shoot it with the bow, then use the Longshot to cross through the gate before it shuts.

Beyond the gate, use the ceiling target to reach the underwater passage. Pull the submerged block out, loop through the passage again, and push the block aside from its other face. Follow the newly opened space to the key chest.

Which crest do I need?

Follow the blue path to Ruto’s shaft to lower the water. Follow the green path to the crest inside the central pillar to bring it back to 2F. At each crest, play Zelda’s Lullaby. The route under the floating block is optional for collecting keys.

Pick up the route from your current water level

• Low water, floor exposed. Finish the torch room and dragon-mouth gate first. When those chests are open, head into the central pillar. Use the grapple target above you to reach the green crest and play Zelda’s Lullaby.
• Middle water, level with the 2F doors. With the short Hookshot, check the cracked wall east of the hub. With the Longshot, use the bow and the north eye gate. Once your key is collected, the pink route leads back to the highest crest.
• High water, level with 3F. If you still need an early key, put on the Iron Boots, descend and take the blue route to Ruto’s shaft to reset the level. If you already hold the Boss Key, stay high. Use the Longshot at the north door and cross the spiked approach in the Iron Boots.

Sources

Nintendo Life’s Switch 2 Water Temple walkthrough identifies the red rupee, the floor routes and the final block puzzle. G2A’s key-location guide lists the four progression chests. Players comparing the remade room also report finding the red rupee.