How do you breathe underwater while building?

Use a Turtle Master potion, a Respiration III helmet plus Aqua Affinity, or build under a temporary water-breathing conduit. The conduit is the best long-term solution.

What blocks should I use for an underwater base?

Glass is essential for ocean views. Use prismarine, sea lanterns, and dark prismarine for an ocean-themed build. Concrete and quartz work well for clean modern underwater designs.

How do you drain water from an underwater build?

Use sponges to remove water quickly. Build walls first, then sponge the interior. Sponges dry in the nether. Alternatively, use a large sand or gravel fill and mine it out after.

Underwater Base Guide

Overview

Underwater bases offer one of the most visually stunning living experiences in Minecraft. Floor-to-ceiling views of ocean life, protected access to ocean monuments, and the unique aesthetic of aquatic lighting make underwater bases a rewarding mid-game project. The challenge lies in water removal, structural integrity, and access management.

This guide covers how to build a fully functional underwater base with a glass dome, bubble column entrance, interior farming, and integration with a conduit for underwater breathing.

Preparation and Required Items

Before starting construction, gather these essential items: a stack of glass blocks, a stack of sponge (from ocean monuments), a respiration III helmet, at least 3 water breathing potions (8-minute extended duration), a conduit, and prismarine blocks for the conduit frame. Doors are essential because they create air pockets underwater.

Build a temporary underwater shelter first. Place a door underwater and open it to create an air pocket inside. Use this as your staging area.

Dome Construction

A glass dome is the most visually striking shape for an underwater base. Start by creating a scaffolding ring at the desired dome diameter. A 15-block diameter dome provides ample interior space. Build the dome layer by layer using glass blocks, working from the bottom up.

Once the dome shell is complete, use sponges to remove water from the interior. Place sponges on the floor and they absorb adjacent water source blocks. Dry wet sponges in a furnace. For a 15-block dome, expect to use 15-20 sponges.

Interior Design and Farming

Inside the dry dome, build a multi-level interior. The ground floor houses your main base functions: crafting area, furnaces, storage room, and enchanting setup. Use prismarine or sea lantern blocks for lighting that matches the aquatic theme.

Build a kelp farm on the second level using sand blocks with water source blocks above. Kelp grows rapidly underwater and can be smelted into dried kelp blocks for fuel. Add a coral reef garden using coral blocks, sea pickles, and seagrass for decoration.

Bubble Column Entrance

A bubble column elevator is the most efficient entrance for an underwater base. Build a 2x2 vertical shaft from the surface down to the dome entrance. Place soul sand at the bottom of the shaft to create upward bubbles. When you swim into the column, you are instantly propelled to the surface.

For the downward entrance, place magma blocks at the bottom of a separate shaft to create a downward bubble column. This pulls you down to the base entrance quickly.

Pro Tip: Build your base near an ocean monument to harvest sponges and prismarine. The elder guardian drops wet sponges and the monument structure itself provides thousands of prismarine blocks for decoration. Use the conduit to gain water breathing, night vision, and haste effects within a 32-block radius, making underwater construction much easier.