Even though soaking tubs are fairly simple and easy to clean, especially if they are made from fine quality materials, they can sometimes scratch, or the color can fade if you use the wrong tools. The best way to clean a soaking tub is to get a tub cleaner and a brush with gentle bristles.
Also, you can try DIY techniques, such as a dilute solution of vinegar to remove any unpleasant stains. If you clean your tub frequently or after every use, you will not have to worry about deep scrubbing or stains. You need to wash your soaking tub thoroughly, especially if you use bath salts and oils frequently.