That is what I meant to say if I did not. Use the drain pipe for your conduit. If it is a drip circuit you do not need the pressure rating of PVC although you are not talking a huge difference in cost I guess. You probably want PVC on the potential pressure side of the valve though. I would check that that valve is rated for low flow while you are at this?
Might want to note or sketch what you did somewhere for the new homeowner that follows you.