It has 2 regular slides, the kind you might see at a playground. They don't come out of the volcano. I don't think they have water running down them. Its best to get wet first, then go down the slide.
There isn't any kind of age or height requirement. I wouldn't recommend going down the slide with a small child. I think the slides are enclosed tubes, so it would be hard for an adult to sit up straight. The slide "dumps" you into the deep end...maybe 5 feet. (Can't remember how deep) Not a shallow landing spot. You'd land on top of a child if you rode together. You could wait in the water and scoop your child up after they hit the water.
Someone correct me if I'm wrong. Its been a few years since we've stayed there. They may have changed things since then as well.
I hope that helps and doesn't confuse you further. If someone has photos they could post, you'd know what I'm trying to describe.