I had tried bait fishing at Bethul which is south of goa near the cavelossim area. Did not get any bites on the particular day, But my cousin and his friends who are locals have caught loads of fish in 3-7 kgs size.
Also u can try the river along the cavelossim area. There is a nice hotel called THE FISHERMAN'S WHARF" by LE MEREDIAN which is along the bank and they also have a barge which goes into the river for around 30mts. So u can fish all day long with beer being served
I had fished in the same place for 3 hrs and missed a big fish as i could not handle the rod
, it was my first time ever at fishing.
All the best for ur trip and tight lines.