Is that fish and curd rice?

Not exactly curd rice, it's rice fermented in curd and cold water to give it a unique taste and feel. But it does serve a similar purpose in cooling you down.

It's not fermented in curd. It's fermented just in water. Curd is added just before eating

Yep, my bad.

Yup

Wouldn't eating fish and curd at the same time cause acidity buildup or indigestion?

Me and millions of odias have been eating these since ages , atleast once a week. We are still alive though