Hmmm... The tank looks very nice... and i hope you can maintain it well. Your going to have to measure the PH constantly due to the Drift wood in the tank. If that driftwood is real, it will lower the PH, and soften the water of your tank. As u know... Tang tanks are high in PH and Hardness, and the cichlids will be uncomfortable. The only ones who will enjoy your creation would be, if you decide to get them, are the Plecos. (This is only if you don't constantly monitor the water.) I would add some holey rock, limestones, and maybe make a few custom ornaments with dolamite or something like that to raise the PH and Hardness to offset the woods acidic properties. Just some suggestions to keep your future cichlids happy.