Can you create two tiles high water lock in here?

[SackMaggie]

I want two have a two tiles high water lock in the red circle. Normally I would use salt water and water but It wont stable when I try it (always displaced)

So any Ideas on how to achieve it?

BTW I was trying to design a 96 tiles stable layout that can use empty space to store water.

Spoiler

Change to one tile gap

 

[Zarquan]

The situation you have in your last image is actually air tight, though it doesn't look like it,  Gases only move horizontally, so it can't squeeze past the salt water to get to from top to bottom or vice versa.  But this won't stop the pip.

If you were trying to create a 2 tile airlock in this situation, it is failing because of Liquid Bypass, a special liquid-gas mechanic added in to the game for when you have gas stuck right next to a perceived opening above.  If you have water above your salt water, it will swap with the gases to the left or right of the salt water.  So, in this configuration, you can't create a 2 tile high waterlock unless the bottom chamber is a vacuum.

This is a very powerful mechanic and I use it all over the place in my bases.  A good resource to understand this mechanic and how it can be used for your benefit can be found here: 

You could try multiple drops of water to the left and right and a door to contain the pip while maintaining access to the outside.

I like your idea for multipurposing the room, but I will note that ranches can have industrial machinery like refineries and power generators in them.

[SackMaggie]

@Zarquan I vacuum the bottom chamber like you said and put a 3 tiles water lock instead, And its work like a charm!

Spoiler

Edit
I noticed the auto-sweeper not reached the bottom tile(salt water tile) So back to changing layout again and this is what I got.

[Ntr1cate]

5 hours ago, SackMaggie said:

I noticed the auto-sweeper not reached the bottom tile(salt water tile) So back to changing layout again and this is what I got.

turn it vertically and place it half into the water