Tapioca flour is readily available here in the philippines its cheap and its everywhere. So i have been doing some research cassava or tapioca starch is resistant starch (correct me if im wrong) its not digested by the small intestines and directly goes to the colon which ferments and fuels the good bacteria and produces butryte that helps to heal or protect the colon (this is my understanding from my research).
My daughter was having D two weeks ago no blood and mucus but lately was having a little mucus and blood 
pedia GI ordered a stool culture results came back heavy growth of enterobacter cloacae she was put on cefixime antibiotic. I experimented with cassava flour for the 1st day mixing it with my daughters food and milk morning and evening. No promising results for 2 days pedia GI ordered cbc to see if my daughter's wbc is high it came back positive and changed her antibiotic to ciprobay. I continued adding cassava flour plus added potato starch 1 teaspoon each usually she takes her ciprobay at 8pm then i give her P. reuteri (probiotic) 10pm when she asks for milk (thanks to pb4) and when she asks for another milk 2-3am i will add the starches.So the results for 2 days now was pretty good no blood and mucus (knock on wood) but its not yet formed going only 2x a day. Maybe the ciprobay is doing its job and maybe the RS is helping also, i will do a stool culture and cbc tomorrow to see if there are any changes and will keep you posted.
Im currently looking for Hi-maize flour its resitant starch also and will try to mix it with cassava and potato starch. Wish me luck its just been 3 months of remission for her and i hope and pray we can continue it to be that way. 
daughter anya 2yrs old Dx with indeterminate colitis 4/07
,Pentasa 250mg 1x/day, probiotic, flaxseed oil, multivitamins, iron, immuzinc, barley green.