I've been trying unsuccessfully to create my sourdough starter. First of all it starts off well, i combine 100g of bread flour with 100g of water (bottled) mix well and leave it in my jar covered with cloth for 24 hours. Next day i always have a bit of action in my jar, so i feed it another 100g both of my water and flour and leave for another 24 hours. So on day 3 my starter has gone crazy doubling or even more in size and shrinking again by the time the 24 hour period is up. Next step is where my starter dies every time, I discard half and add another 100g of flour and 100g of water. After a further 24 hours there are slight bubbles but not much life at all, so i continue the process but never get anywhere close to action i was getting on day 2 and 3. Can anyone tell me why my starter is dying when i do the "discard and feed" process?