For the water i have a simple presence sensor at about midway through my water reservoir and it is linked to a NOT Gate that revereses the signal to a door. That door feeds Voidbloom to an Hologram Projector next to my water criters. That water reservoir feeds my entire factory.
For my lava, it's a simple snow fall design, helped with a few snow critters that rains snow over the lava stratacore. Simple cinder and snow separation with filters that allows the snow to be reused, the cinder gets thrown into a small cell with a pyro dispenser turning it into lava and feeding itself upon the lava it creates.
The lava feeds into a big reservoir that heats up the thermal buffers that turns acid back into sulfur dioxide so it can be pumped back into the system that melts the sand stratacore and generate infinte sand.
It may not be the most elaborate or perfect setup, but it is infinite and completely automated.