SOLVED: Copper Union -- Suggestions on How Best to Disconnect

[Zmonet]

I have a failed booster pump that connects to my well tank. The booster pump has failed, and I need to replace it. I've disconnected one end of the booster pump but am struggling with the compression copper fitting at the well tank end. Any suggestions on how to best disconnect it? It seems stuck, but it is possible I'm not using enough force.

SOLVED: Turns out I just needed to use a little more force.

 

[Reach4]

Glad it is loose. I would have suggested two longer wrenches. With the handles slightly offset from each other, you can pry between the handles.