Distance of buffer tank to ground source heat pump

But that doesn't solve my space problem, does it?

A 300l tank already requires much less space than 1x180 + 1x120. But I think you should have understood the main part of the solution (Pufferspeicher einfach weglassen) by now...

Are there geothermal heat pumps with a 300-liter tank? I did not find any in my research.

Are there geothermal heat pumps with a 300-liter storage tank?

Storage tank separate. Of course not as a combined unit.

Maybe a combination storage tank would be a solution? We are getting a Juratherm HDWPU 400 (300l hot water + 100 buffer storage). Has anyone had experience with Juratherm?

Huh, now I’m lost. :-)

We planned 180 plus 120. Why should I now add a 300-liter tank next to the 180? :)