Sorry if this is not a good forum for this question, but I thought maybe I might get some answers here. I've got several bottles of acrylic paints (for decorative painting) that I haven't used in about five years. A lot of them are very thick now and kind of crusty on top underneath the cap. I can clean the dried top layer, but is there any way to salvage the thickened paint to make is usable again? I'd really hate to have to throw all these out if there is a way I can bring them back to usable condition. Thank you so much.