Zeke The Black Ghost Knife Again! More Questions!

[zeke the black ghost knife]

tank mates! wut can be my knifefishes best friend? probably so far hes in love with my lyertail. (lol he'll eat his girlfriend) can anyone PLEASE tell me wut can be his best friend! wut im aiming for is none bgk edible, none agressive and friendly, and will look good in my aquarium!
for help, heres some info

aquarium size:90 gallon
tank mates:red tail shark ,lyertail, 2 gouramis, buenos aires tetra, mollie, pictus catfish
habitat: open swimming with 3 caves and a driftwood.
type of tank:community

 

[zeke the black ghost knife]

anyone here? i really need info!