How to convert density from [g/cm3] into fluid gradient of [ psi/ft ]?

1 g/cm3 = 0.26 psi/ft

1 psi/ft = 3.833 g/cm3

\frac{1\;g}{1\;cm^3}\;\cdot \;\frac{2.54\;cm}{1\;in}\; \cdot\; \frac {12\;in}{1\;ft} \;\cdot \;\frac{6.452\;cm^2}{1\;in^2} \;\cdot\; \frac{1\;lb}{453.59\;g}\;=\;0.4335\;\frac{psi}{ft}

This is in agreement with what you what have found with a simple Google search (http://www.google.com/search?source=ig&hl=en&rlz=&q=psi%2Fft&aq=f&aqi=h1g10&aql=&oq=#sclient=psy&hl=en&q=psi+ft+water&aq=1&aqi=g5&aql=f&oq=&pbx=1&bav=on.2,or.r_gc.r_pw.&fp=af05b79bb255a75f).