InCharge & LivingBlessed are quite right in this thread and in answer to your post.
Herbal teas are a source of external nutrition and you will therefore be undertaking a reducing and malnourishing diet with the risks that that entails.
Full ketosis will not be reached, and the resultant benefits will be much reduced. Some have even described this as a "starvation diet" (which it is) as the body will not be utilizing its food reserves economically.
The body also has its own inimitable way of preserving all food elements such as minerals and vitamins on a water-only fast, so supplementing with the same is totally unnecessary. For example it is said that you need Vitamin C or Ascorbate on a daily basis while eating, otherwise there is a risk of developing scurvy, but no water-fast of any length of time has ever produced this deficiency disease, whereas a limited diet has been proven to do so.................