I wouldn't recommend putting shellies in as I had caudos and ending up front food
Oh and I have two regani at 9 cm who breed constantly in there
The whole breeding thing is a tough one for me. I like to have a nice looking display, which will end up including some decent rockscape (yet to be designed). This makes recovery of holding females difficult at best, especially in a 2.5' deep tank that is 6' long. I completely gave up on the Tropheus in that regard. They would breed constantly, and most of the fry ended up as food. I had a pile of rubble-fist sized rocks at one end of the tank, designed to be a refuge for fry, which worked nicely. Then I would regularly find fry in the weir, which would get netted and transferred into the grow-out cube. But now that I'm getting something a bit more fancy (F1 fronts) etc, letting nature take its course seems wasteful. But catching holding females seems like it's going to be major challenge, as is catching hatched fry from Calvus etc.