Low viscosity fluid impact to DH of centrifugal pump

[Nickchen007]

I know that high viscosity fluid will make the DH of pump decreased, and I did found the correction methodology in reference book. In the other hand, I think the lower viscosity (than water) may make the DH of centrifugal pump increased. Let said a fluid with 0.2Cp viscosity may have a 5% high DH than the performance curve (made with water). But I don't know how to correct it. Does anyone have such experience to correct the DH curve of centrifugal pump for low viscosity fluid?