Ekadashi fasting is observed on every 11th Tithi in Hindu calendar. There are two Ekadashi fasting in a month, one during Shukla Paksha and another during Krishna Paksha. Devotees of Lord Vishnu observe Ekadashi fasting to seek His blessings.
Ekadashi fasting spans for three days. Devotees take single meal in the afternoon a day before fasting day to make sure there is no residual food in the stomach on next day. Devotees keep strict fast on Ekadashi day and break the fast on next day only after sunrise. Eating of all type of grains and cereals is prohibited during Ekadashi fasting.
Devotees can choose to observe fasting without water, with only water, with only fruits, with one time latex food according to their will and body power. However it should be decided before starting the fast.