A head for a peristaltic pump that may be used for delivering ink to a flexographic printing press includes a housing and a roller assembly. The housing is adapted to receive a flexible tube. The housing has a curved wall and a clamp. The clamp secures the flexible tube within the housing. The roller assembly is rotatable within the housing. The roller assembly includes at least two compression rollers and at least one guide roller. The guide rollers are peripherally spaced between the compression rollers where each of them comes into contact with the flexible tube during rotation of the roller assembly. The guide rollers guide the flexible tube to stay centered with the compression rollers and initiate decompression of the flexible tube to return to a partial compression dimension. Fluid is moved through the flexible tube by rotation of the roller assembly.