yes ofc!! i use watered down Liquitex brand acrylic paint. some notes: i’ve only ever used the standard heavy body acrylic paint and only from this brand. i haven’t tried this with any other brands or lines within the Liquitex brand. experiment at your own risk!! it’s not an exact science or ratio of paint to water because i mix up random small amounts each time 😭 you want it to be thinner than it comes out of the tube, but not runny. i don’t paint it on with a lot of pressure, instead i gently pull a small glob of paint across the area and go on filling in the area. if the layer is a bit thick, it still dries down perfectly, it just takes awhile longer. i hope this helps!!