Diagnosing the Problem. If leaves on an aloe plant develop dark spots, it's critical to diagnose and correct the problem quickly. The most likely cause is too much water, which promotes growth of fungal microorganisms that cause spotting of leaves.
If you're painting Plexiglas, not just any paint will do. Some paint may not adhere well, if at all. Acrylic paints work best on Plexiglas, and spray paints designed for plastic work as well. Clean the Plexiglas with water and a mild soap such as liquid dish soap, rinsing it off thoroughly afterwards. If your goal is for the paint to adhere well, scuff it up with a fine-grit sandpaper; paint doesn't adhere well to slick surfaces, so the sanding gives the paint something to grip.
When cleaning plexiglass, it is important not to use any kind of chemical cleaner that contains ammonia since it will harm the plexiglass acrylic. Cleaners such as Windex or 409 should be avoided at all costs. A person should also be careful not to use their bare hand or a dry cloth to clean plexiglass. Any dust or dirt should be blown off, and then a slightly damp, soft cloth can be used with the homemade plexiglass cleaner. Children are also problematic when it comes to plexiglass and need to be taught that hard toys will damage the plexiglass surface. Deep scratches are difficult to remove from plexiglass, so it's best to keep the plexiglass item in an area where it won't have contact with sharp objects. Learn more about Cleaning Products