Yes, that is due to magnesium deficiency. You do take mag. supplements dont you?
If so not enough. The best way to evaluate how much to take is just enough so as to get 2 to 3 bm on the following day. Depending on how much fiber/acidic food you eat, this will vary from day to day. so keep adjusting your mag level to your needs. This is an important aspect of helping the toxins/ candida out.
The best mag to start with is Chloride magnesium, simply because liquid assimilates better in a colon full of candida threads. The taste sucks, but diluted in a full glass of water it is not that bad.
If you get diarrhea, it means you are doing much better and should reduce the mag intake.