It is all set up. The only issue I am having is that my solenoid won't hold back the pressure of the RO water.

It leaks right through.
And it is supposedly rated to 150psi!
Any my holding tank has a max pressure rating of 100psi.
At the bottom of the page:
http://www.mcmaster.com/catalog/108/html/0375.html
Delrin Direct-Acting Solenoid Valves
ââ"šÂ¬Ã‚¢ Normally Closed (valve opens when energized)
ââ"šÂ¬Ã‚¢ Minimum Differential Pressure: 0 psi
ââ"šÂ¬Ã‚¢ Maximum Pressure: 150 psi
ââ"šÂ¬Ã‚¢ Maximum Temperature: 200Ã"šÃ‚° F
With Spade Connector
Only 1 1/2" in overall length, these valves are for use with water, oil, and inert gas. Body is Delrin (acetal) and seat is nitrile. Coil is Class F. Choose valves with 18" double leads or valves with spade connectors. Mount vertically with coil on top. Current draw is .62 amps @ 24 VAC, 60 Hz; .18 amps @ 120 VAC, 60 Hz; or 1.22 amps @ 12 VDC.
Connections: NPT female.
To Order: Please specify 24 VAC, 120 VAC, or 12 VDC.