I have a 110 extra-high fish tank with 15 serpae tetras, 8 silver hatchets, two bolivian rams and a bristlenose pleco.

I’m having trouble keeping small schools of angelfish alive in this tank. I’ll put 5-6 angels in there, and within a couple weeks they tank on me (no pun intended). With no problems regarding water chemistry and otherwise good husbandry on my part, I’m blaming it on either overcrowding of multiple angels or, more likely, aggression from the serpaes.

Any thoughts on 1 or more "centerpiece" fish that I might try?

Thanks.

C