I planned on changing for gravel to sand in my 120 gallon mbuna tank and I finally did it yesterday. It took forever. Had about 30 mbuna in there. First thing drained half the water out, took all the rocks and decorations out. And then attempted to take the fish out and move them to a ten gallon setup. It was extremely hard getting the fish out a lot harder than I expected. When we finally got the fish out we took out the gravel. Next I put in two 50 pound bags of pfs and then 30 pounds of aragonite sand. Clouded the water up pretty good so I filled it back up with the filters on for awhile. When it was clear enough to see round there I until the rocks and decorations back in. I tried to make it look a little more natural although I know there are some fake looking things in there.
Then I went to the airport to pick up the fish I ordered from cichlid express. So by the time I came back and acclimated them to the tank it was clear enough for all the fish to be put into the tank. All still look healthy and are doing fine so far. There's about 45 fish in there now. I'm hoping it won't be too big of a shock to the water and filters since I took all the original gravel out. I have an fx5, xp4 and f306 so it's got good filtration and water movement. Let me know what you think, I'll take some suggestions as well
The first picture is the old setup