Push/Pull pump for larger water changes?

[Richmond]

Good day. My saltwater reservoir is in my garage and about 50 feet from my tank. I have a pex line run to the tank under the crawlspace in the house. It works great.

The only downside is that water sits in the pipe, until the next water change.

I'm looking for any pump possibility (not a dosing pump) that can push water from garage to tank, then pull the line clear when it's done. Does this exist?

Thanks in advance.

 

[Jeffcb]

Very expensive but I was looking at this one.