for a 3/4" bulkhead..what size 90 PVC do i use

[05XRunner]

Ok so I want to make up my pluming with PVC pipe and get rid of the rubber tubing..So what size PVC pipe do I use to go over the threads on the back of a 3/4" bulkhead...1" PVC??

this type of bulkhead

http://www.aquacave.com/075-bulkheads-438.html#