> For the complete documentation index, see [llms.txt](https://create-deep-seas.gitbook.io/create-deep-seas-wiki/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://create-deep-seas.gitbook.io/create-deep-seas-wiki/deep-seas/diving/ballast-vent.md).

# Ballast Vent

<img src="https://1371052705-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FV22FKtcNjWW37kUFLLdR%2Fuploads%2Fgit-blob-4332a209ff719786316b2d34015c63e60fcad284%2Fballast_vent.png?alt=media" alt="Ballast Vent" width="128">

The Ballast Vent is the sea valve of the submarine. It is the only way to get sea water into the [Ballast Tanks](/create-deep-seas-wiki/deep-seas/diving/ballast-tank.md) and back out.

## Recipe

![Ballast Vent recipe](https://1371052705-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FV22FKtcNjWW37kUFLLdR%2Fuploads%2Fgit-blob-a8f21fd04dddc55b2ee7c140d34e85314bf13aa8%2Fballast_vent.png?alt=media)

## How to use it

1. Place the vent in the hull with at least one face touching the sea. If no face is in the water, there is nothing to pump.
2. Connect a pipe to it, on any face. The vent needs no rotation and no redstone.
3. Put a pump between the vent and the tanks.

A pump pulling from the vent draws sea water in and fills the ballast, the submarine dives. Turn the pump around and it pushes the water back into the vent, which dumps it into the sea. The ballast empties and the submarine rises.

With an [Onboard Computer](/create-deep-seas-wiki/deep-seas/diving/onboard-computer.md) on board, use [Pump Controllers](/create-deep-seas-wiki/deep-seas/diving/pump-controller.md) instead of plain pumps. They pick the direction and the speed on their own.

## Good to know

* A face with a pipe on it is closed. The faces left open are the ones that take water from the sea.
* The vent counts as the sea: it never runs dry and never fills up.
* Bubbles come out of the open faces while it works, so you can see it from outside.
* It holds down to 400 m.

{% hint style="success" %}
**Details to look for**

* You can see it work from outside: bubbles get sucked in while it fills the ballast, and a splash of water comes out of its open faces while it empties it.
  {% endhint %}

## Video

{% hint style="info" %}
Video coming soon.
{% endhint %}