Nirjala fast, i.e., Total fast even without water is not compulsory on all ekadasi days. You can observe Parital Fast  itself that will also be good.  If you are properly observing Partial fasts for all ekadasis, you need not observe Nirjala Ekadasi in June every year.  In such cases, you can observe partial fasting even on Nirjala Ekadasi. Take then following on ekadasi days after offering to Krishna: Milk, milk products, fruits, boiled ground nut, vegetables, etc, without grains.  Avoid Grains, Onion, Garlic, Meat, Nuts (except groundnut), mustard seeds, etc.  You can use salt, sugar and Sun flower oil (Not other Oils) in small quantities. Avoid any Grain though it is Krishna Prasadam. Offer only grainless food to Krishna on ekadasis. Anyone who is aged above 75, who is bed ridden, who has acidic and ulcer, who has Blood pressure, Heart issues, tumour, diabetes, kidney issues, etc., who have been advised by doctor not to fast may avoid fasting. Worship Krishna...