I really don't want to upset you in any way so please feel free to disregard my reply. Fasting can be very dangerous and you can become very malnourished. Your body will turn to your muscle and feed on itself and that will eventually lead to a slower metabolism. If you can eat so little, why not eat a balanced diet and lose weight in a way that you can maintain? If you starve yourself, you'll most likely end up binge eating from your sense of deprivation and end up gaining it all back and then some. I hope you'll reconsider your plan and choose something that is healthy. Veggie chips and water are not giving your body the nutrition it needs.
Also, the weight fluctuations are likely due to water retention and losing weight on the scale doesn't necessarily mean you're losing fat.
First goal: under 180:
Second goal: 175 or below:
Third goal: 168 (no longer overweight):
Fourth goal: 160 or below:
Final goal: 145-155 (not sure if this will ever happen):