Yeah, Paully, put another pike in there. Make sure it is the same size as that little one, matter of fact, find two more pikes that are tiny, add them to the mix. With that dense planting, eye contact would be minimum so I bet they would all work, plus they will have a chance to grow together. Some Johanna would work, Xingu I (although this one may be rowdy), maybe some other Sax species, if you can find any Species Crenicichla Saxatilis, jump on those, or Frenata......both very nice looking