Huge brawl on "Real Housewives of Atlanta" ... sources tell TMZ.
"Real Housewives of Atlanta" cast member Brandon DeShazer -- Kenya Moore's assistant -- was seriously roughed up last night by Phaedra Parks' husband Apollo Nida ... all over beef stemming from some dumb workout video, a witness tells TMZ.
According to witnesses, Apollo flew into a rage and "violently attacked" Brandon at a party that was being filmed for the upcoming season ... and it was all caught on tape.
The witnesses say Apollo -- who once served 5 years in prison for racketeering -- had to be restrained by 7 male crew members before finally retreating.
We're told Apollo was pissed because Brandon and Kenya had allegedly agreed to produce a workout video starring Phaedra, but instead produced their own, cutting Phaedra out. We're told Apollo felt slighted, and blamed Brandon for stabbing Phaedra in the back.
Apollo has a different story, telling TMZ, there was a fight on the set, he tried to break it up and got attacked by Brandon. Apollo says at that point he defended himself and everything got out of control.
Calls to Bravo weren't returned.