Marc Anthony and Jennifer Lopez's love affair may not have lasted in the U.S., but the two are making it work on their journey across Latin America as they film for their Univision TV series, ¡Q'Viva! The Chosen .

"We have a great relationship," Anthony, 43, said in an interview with " Good Morning America" contributor Chris Connelly.   "There's a certain shorthand.  It's how we started, when we started working together."

Lopez and Anthony announced the development of the "American Idol"-style talent competition when they were still married but began shooting it after they confirmed in July that they had split , after seven years of marriage.

Even amid reports the two are feuding over custody of their 3-year old twins, Anthony said  he had no hesitation that the show must go on.

"Not for me," Anthony said.  "The question was, what would it be like, having to go through this whole process in the middle of what we were going through."

"But, it was just like, 'Hey, what's up? How's everything? Ah, good,'" he said.  "It's just, Jen, Jennifer is Jennifer."

That kind of "shorthand," as Anthony calls it, can be seen in the first episodes of the 12-episode series that follows Lopez, Anthony and director Jamie King as they travel throughout 21 Latin American countries auditioning singers, dancers, musicians and street performers to compete to be part of a live Las Vegas show to celebrate Latin America culture.

"It wasn't difficult at all for me," Anthony said of working with his ex.  "I don't know what she would say. … God knows…"

Lopez did have something to say when the couple reunited in Puerto Rico after traveling apart for casting, and Anthony went gaga for a pair of big-busted twin sisters.

"I don't know," Anthony, said  laughing, as to why his ex gave him a look after that audition.  "I have an idea."

Anthony also laughed when asked about J.Lo's likening their post-split relationship to that of Sonny Bono and Cher  but described their happy, working relationship in another way.

"It was like, you know, just riding a bike," Anthony said.  "It was just us … and we're very much like that."

"We always made each other laugh," he said.  "You know, don't take things too seriously, just always busting each other's chops."

More difficult than working with his ex, Anthony says, has been learning to say no to people in auditions, something Lopez was already well trained in her other job as one of three "American Idol" judges.

"I really underestimated how uncomfortable it is to say no," Anthony said.  "Jennifer had brought it up on her first season of 'Idol.'  I was like … 'Just say no,' but she's like, "No, it's not that easy."

"She probably had the most experience of all of us in saying no," Anthony said, joking.  "I was like, 'there she goes.'"

ABC News' Chris Connelly, Bill Cunningham and Taylor Behrendt contributed to this report.