Christopher Knight Files for a Very Brady Divorce

The "separation" is over ... and now former "Brady Bunch" star Christopher Knight has finally filed for a divorce from his reality star wife Adrianne Curry ... TMZ has learned.

Back in May, the two announced they were separating to rethink the marriage ... but now, it appears Knight has reached a decision -- and he wants out.

Knight filed divorce papers in L.A. County Superior Court on August 19 ... according to court records obtained by TMZ.

Knight married the "Top Model" winner five years ago ... after they co-starred on "The Surreal Life" together.

A rep for the couple tells us, "They are amicable and remain friends."