I use egg crate /light diffuse panels, 12 bucks for a sheet at home depot and such, cut to size with diagonal snips, then wedge in place with a piece of hosing off the the python hose. just a short piece to wedge between the glass and divider at the top of the tank.
Because my cichlids can be quite pushy, and will easily knock down an insecure divider, I'm very careful. I use horizontal pieces zip tied below, and vertical pieces running perpendicular to the main panel to aid in stability.
I also notch out spaces so the egg crate can be jammed between rim of the tank top border.
I also put heavy rocks on the horizontal panels.
pretty cool duanes, so far my male jag about 13" has not been able to knock mine down, but does not mean it will not happen at some point trying to get to the female between spawns.