Water flow in Tanganyikan tank

[CRBINWPB]

I have a 55 gallon corner tank (pie shaped) filled with Lake Tanganyika cichlids. I am using a fluval canister filter (306) . I want to add to the water flow and am thinking of a Cobalt Power head. Where and at what depth should it be placed. I have 3 different rock piles one on each side and one in the corner. thank you for your advice
CRBinWPB.

 

[Drew@HStreetNE]

Sicce makes some smaller solid options. Have you looked into those at all?