One of the side effects of total colectomy is diarrhea and sometimes even fecal incontinence.
Due to surgery of colon cancer, and changed anatomical structure of GIT, patient experiences changed bowel function.
One of the main goals after colon or colon-rectal cancer's surgery is to have high quality of life by getting control of bowel movements.
Colon main function is absorption of liquids.
Because, parts of the gastrointestinal tract are removed with the surgery, there is a shorter tract for absorption the liquids (with total colectomy the absorption function is totally impaired) and that's causing a shorter transit time of food trough the GI tract and changed consistent of stool. This results in having more frequent bowel movements per day. Normal healthy people, usually have maximum three stools per day, but patients after colon cancer surgery are having more then that in form of diarrhea.
Your father in low should avoid taking liquids during the meal because this will cause more voluminous mass in his tract and shorter transit time through GIT and having frequent bowel movements. It's better to drink liquids between meals.
Because, GIT's absorption function is impair,using a medical fiber can slow down the transit time. Fiber taken right after a meal in very little fluid, can soak up excess fluid in the digestive system and thus slow things down.
He needs to avoid certain foods (spicy foods, sweets, high-fat, hot liquids,some fruits and vegetables), because he'll have increased bowel movements.
Does he experience inability to fully empty at one specific time?
How many meals he has per day?
Was he done ileostoma?
