coffee enemas are great for brain fog (so is a lot of drinking water). The only reason people say enemas are "bad" is because you can become dependant on them. I would not do 3 a day but I think that an enema a day is quite reasonable during the first few week, then reduce to one every second day when you can manage.
Sciatic pain and other nerve issues can be related to a few different things. Lecithin supplements (one with every meal) is very helpful for nerve protection (but also for other importtant cell function so keep going until your over candida).