What a conduit does and why you need one

A conduit is a block in Minecraft that gives you underwater breathing and night vision when you're near it. It also damages hostile mobs that come close. You build it by placing a heart of the sea in the center of a 3×3 frame made from prismarine blocks, dark prismarine, or prismarine bricks — any mix of those three works. Once built, it needs to be surrounded by water to activate.

The main reason to build one is survival underwater. Without a conduit, you can hold your breath for about 15 seconds before taking damage. With a conduit active, you can breathe indefinitely as long as you stay within its range. The effect extends about 32 blocks in all directions from the conduit, which is roughly the size of a small base or mining area.

Conduits also deal damage to any hostile mobs (like drowned or guardians) within that same range, which makes them useful for defending underwater structures or farms. The night vision effect is a bonus — it lets you see clearly in dark water without torches.

Key Takeaways

  • A conduit requires a heart of the sea in the center and a 3×3 frame of prismarine blocks, dark prismarine, or prismarine bricks around it.
  • The conduit must be completely surrounded by water to activate and provide its effects.
  • You can find hearts of the sea in buried treasure chests, which are located using treasure maps dropped by drowned mobs.
  • The conduit's effects reach about 32 blocks in all directions, so place it in a central location if you're protecting a large area.
  • You can stack multiple conduits to cover a bigger area, since their effects overlap.

Finding a heart of the sea

The hardest part of building a conduit is getting the heart of the sea, since there's only one per buried treasure chest. To find buried treasure, you need a treasure map, which drops from drowned mobs when they die. Drowned are zombies that spawn in water, most commonly in ocean biomes or in dark water underground.

Once you have a treasure map, hold it in your hand and look for the X marked on it. The map shows your current location and the treasure location relative to each other. Dig down at the X — the chest is usually buried 2 to 5 blocks below the surface. Open it and take the heart of the sea. If you're playing on a server or in a world with other players, treasure chests can be looted by anyone, so you may need to search multiple chests.

If you don't want to hunt for maps, you can also find hearts of the sea in the creative mode inventory or by using commands like /give @s heart_of_the_sea in survival mode if cheats are on. In pure survival without cheats, treasure hunting is your only option.

Gathering prismarine blocks

Prismarine blocks come from ocean monuments, which are large structures that spawn in deep ocean biomes. Inside and around the monument, you'll find prismarine, dark prismarine, and prismarine bricks. You can mine them with any pickaxe, but a diamond or netherite pickaxe is fastest. They drop as blocks when mined, so you don't need silk touch.

You need 16 prismarine blocks total to build the frame: 8 for the bottom layer, 4 for the middle layer, and 4 for the top layer. You can use any mix of the three prismarine types. If you want to avoid ocean monuments (which have guardians that deal heavy damage), you can craft prismarine blocks from prismarine shards and prismarine crystals, which also drop from guardians and sea lanterns in the monument.

Alternatively, if you're in creative mode or have access to a creative inventory, you can simply grab the blocks you need without mining. In survival, the ocean monument route is standard, though it's dangerous — bring healing potions and a good sword.

Building the frame structure

Place the heart of the sea on the ground or on a block. Around it, build a 3×3 frame of prismarine blocks. The heart goes in the center, and the 8 surrounding blocks form the bottom layer. Then place 4 blocks in a 2×2 pattern directly above the heart (one block up), leaving the center empty. Finally, place 4 more blocks in a 2×2 pattern one block above that, again leaving the center empty. The heart of the sea stays in the middle the whole time.

The structure looks like a plus sign or cross when viewed from above. The heart sits at the very center, and the prismarine blocks surround it in three layers: bottom, middle, and top. All 16 blocks must be prismarine, dark prismarine, or prismarine bricks — no other blocks work.

You don't need to place blocks in any special order, but it's easiest to build the bottom layer first, then the middle, then the top. Make sure the heart of the sea stays in the center the entire time.

Activating the conduit with water

Once the frame is built, the conduit won't activate until it's surrounded by water. You need to flood the area around it. The easiest way is to dig a hole or build a chamber around the conduit and pour water into it using a bucket. The water must touch the conduit block itself — it can't just be nearby.

If you're building underwater, the conduit will activate as soon as you place the last block and water is already present. If you're building on land, place the frame first, then add water. You can use a single bucket of water and let it spread, or build a small pool around the conduit. The water doesn't need to be deep — even one block of water touching the conduit will activate it.

Once activated, the conduit will emit a beam of light and start giving you the Conduit Power effect, which includes underwater breathing, night vision, and increased mining speed underwater. Any hostile mobs within 32 blocks will take damage over time.

Expanding the conduit's range

A single conduit covers a 32-block radius, which is useful but not huge. If you want to protect or work in a larger area, you can build multiple conduits. Each one has its own 32-block range, and the ranges overlap, so you can cover a much bigger space.

For example, if you're building an underwater base, place one conduit in the center and another 40 blocks away. The two ranges will overlap in the middle, and you'll have coverage across a much larger area. You can chain conduits together in a line or grid depending on how large your project is.

Each conduit needs its own heart of the sea and its own 3×3 frame, so you'll need multiple treasure maps and multiple trips to buried treasure. Plan your conduit placement before you start gathering materials, so you know how many you need.

Frequently Asked Questions

Can I use other blocks instead of prismarine for the frame?

No. The frame must be made of prismarine, dark prismarine, or prismarine bricks. Other blocks like stone or obsidian won't work. You can mix the three prismarine types freely — the conduit doesn't care which one you use, as long as it's one of those three.

What happens if I remove the water around the conduit?

The conduit will deactivate immediately and stop giving you effects. It will reactivate as soon as water touches it again. The block itself doesn't break — it just stops working without water.

How far away can I be and still get the conduit's effects?

The Conduit Power effect reaches about 32 blocks in all directions from the conduit block. If you swim or walk beyond that range, you'll lose the breathing and night vision. The effect is instant when you leave the range, so you'll start drowning again if you go too far.

Do I need to do anything to keep the conduit running?

No. Once it's built and surrounded by water, it runs forever without any fuel or maintenance. It will keep giving you effects as long as you stay within range and the water stays around it.

Can conduits damage me or my pets?

No. Conduits only damage hostile mobs like drowned, guardians, and zombies. They won't hurt you, other players, or tamed animals like dogs or cats.