As the name implies, the primary feature of the room is a central tank filled with water. There are two ledges on either side of the room for Samus to climb up. Parts of the ceilings and walls are shown to be frozen over with ice, due to the malfunction of the climate control system. It can be presumed that the water temperatures would trigger hypothermia in the standard human, although this is not a concern for Samus in her Power Suit. On the floor of the tank is a grid pattern, and the back wall contains a grate through which the water drains.
However, the tank is filled with scores of Skulteras, and since Samus cannot use the Gravity Feature at that point, her movements are slowed, making combat underwater much more dangerous. She can use her Beams and Missiles above the water to kill them, enabling her to clear the tank without taking damage. Samus is required to go underwater, however, and destroy a hatch on the left. This hatch somewhat resembles a Mounted Blast Shield with its five circles in a pattern, although it does not require the Grapple Lasso to remove. Firing a Missile at it will open a Morph Ball-sized hole inside of it. Laying a Bomb inside this hole causes the water to drain. Samus attempts to resist the flow, but is overwhelmed and carried with the current into the previous room.
Once she returns to the Water Tank, she will find that all of the water, save for a shallow pool has been drained out of the room. Two Kyratians confront her here. While Samus is not required to defeat them, doing so allows her to leave the room more easily.
- "Vast ice cavern" (via automatic door)
- Missile Tank
- In a small vent in the near-right corner, above water. Best collected after the water is drained out of the room.
- Page 91
- "Before dropping into the water, edge up to the water and use Search View mode to locate the Skulteras in the water. Pick them off with missiles to clean the tank of pesky Skulteras, then drop down. If you missed any toothy fish, finish them off before proceeding.
- Locate the large circular hatch at the bottom of the pool and blow a small hole in it with a missile. To crack it open completely and drain the water, jump into the hole in Morph Ball mode and drop a bomb. The explosion drains the room and fills the previous room with water, but not before blowing you back into the previous room.
- Climb out of the water and return to the Water Tank. This time, two Kyratians are waiting for you. Take them out quickly and hop up the ledges on the room's right side."
- Tip: "If you find yourself in trouble, use the high ground on both sides of the room to your advantage. Climb up to get away from the Kyratians and use Concentration to replenish health and missiles, or pick off the enemies with missiles from higher ground."
- Missile Tank! "There is a Missile Tank inside a small vent in the near-right corner of the Water Tank. Follow the right wall down until you see it, then pull yourself up into the shaft. Roll over to the Missile Tank to grab it."