Answer

No. In Tivihar Ekasana, you should not drink water at night.

Explanation

In Jain practice:

• Ekasana means eating only once, in one sitting.
• Tivihar means giving up three types of intake: food, water, and mouth-freshening items after the permitted time.

So if you have taken Tivihar, then after completing your Ekasana and after the allowed time, you should not take water.

If you want to drink water at night, that would be closer to Chauvihar exception not applicable—but in Tivihar also, water is not taken after the vow period begins. Traditions may explain timing slightly differently, so it is best to follow your Guru Maharaj Saheb’s guidance.

Takeaway

In Tivihar Ekasana, water is not taken at night once the Tivihar vow has begun.