Are you new? Learn this filter. 5 minute video.

[Lifegrow]

Only one gas can occupy one tile space at a time. A gas pipe works in the same way. So by setting the filter valve to 1g and forever looping for example oxygen, you're essentially filling the pipe to any other gasses that aren't oxygen. Hydrogen cannot go into those looping pipe segments as they're already occupied by oxygen  

That make sense ?

[Saturnus]

I can do one better. Imagine the pipe sections are a table for 4 where all the seats are taken by Mr. and Mrs. Oxygen and their two kids Orville and Orson. Then Mr. Hydrogen can't come for dinner as there's no chairs left at the table.

[avc15]

On 8/30/2019 at 11:27 AM, Gus Smedstad said:

That's a pretty good video covering that kind of filter.

That said, I never use those, because they have too many failure modes.

Pipe back ups are a fact of life for almost all applications. 

It's easy to sense & deal with a full output pipe. However you choose to do it, only run the supply pump when there's demand. 

It's a minor bit of extra leg work.