Stool softner. How many times in a day.

I have anal ulcer, not fissure. My doctor prescribed oral pain killers, antibiotics, and recommended lactifiber - 2 scoops. I drink about 4-5 liters of water and eat about 400gms of fruits, normal food, and buttermilk. My stools are bulky and easy to pass, but the stools are not soft, its not hard as well. It's in roti dough consistency, and it's uncomfortable to pass it, and today, the stools were a little hard, and for the first time ever, i had blood drops in my stools as i passed the stools continuously. I feel lactifiber is not helping me and have decided to quit lactifiber and use Naturolax - A powder. I want my stool to be in paste like consistency so it is easy to pass. Please suggest the dosage i need to consume and how many times in a day.