When Tarek El Moussa and Christina Haack shared, fans of the couple’s HGTV show Flip or Flop said, “How exactly will this work?”

Now, more than four years later, it turns out … maybe not. At least not anymore. While the professional relationship between the formerly married real estate couple seems to be crumbling, will their long-running, fan-favorite reality show experience its demo day in its current format?

“Tarek and Christina don’t agree on anything and have constant tension between them,” a source close to Tarek told E! News. “They argue about everything and can’t stand each other. It’s uncomfortable for everyone and it has gotten worse lately. They just don’t get along and both of them have stated that they don’t want to continue the show together to do the show separately or on their own. “

Earlier this month, the costars and former spouses got into a heated argument while filming Flip or Flop, TMZ reported Tuesday, July 20.