Bitvice is a not a registered tax advisor and you should always seek the advice of a professional tax consultant, as such this should not be considered tax advice.
Currently, selling Bitcoin in South Africa carries the tax implication of either income tax or capital gains tax. This should be personally investigated so as to make an informed decision. Typically however, disposing of an asset over the short term implies that the proceeds of your trading activity will be taxed as income. If an asset is held for the long term prior to being disposed it is more likely to be taxed as capital gains. However, these are situationally dependent.