Yes: you can spray paint the stand with a paint designed for metal. However, be careful with the tank edges. They are probably plastic. So, you will have to determine if the paint will safely adhere to it. A primer may be the best intermediate solution. There are paints made specifically for plastics, but some plastics are chemically resistant to solvents used in paints. Unless you know the specific polymer type of the edges, it will be trial and error. Additionally, try to find a paint that will be water resistant. If it were me, I'd find the best plastic, water resistant, paint I could find and test it on the back edge before applying it all over. When cured, try to scrape it off with your finger nail as a test.