Only ever caught on a lure whilst trolling red & white lures and only red & white, shallow diving and I've tried LOTS of different strategies. Troll usually from Coco Beach round to Fort Aguada & sinquerim and also hugging the coast the other way out the bay (up the mandovi). Also trolled on the opposite bank of the mandovi with success. Barramundi, Grouper, & Snapper. You'll need a very long cast to catch mangrove Jack in Goa because they only libve in Australia, I assume worldfisher meant Red Snapper. Also I'm pretty sure Mahseer are fresh water only & found in just two places in India neither of which are anywhere near Goa so whilst people might like to target them I doubt very much they're gonna catch one, not in Goa anyway, not unless its frozen.
As someone said try the beachcasting I've caught lunch several times off of Candolim Beach near the RP & also up Ashvem but I'm sure most of the coast line will be good. It's a little more sociable for the missus too as if yours is anything like mine then she doesn't like getting up at 5.00 a.m. to meet a boat and neither does she like rock climbing round by the fort so we tend not to go together. What she does like is lying on the beach drinking vodka lime soda and she can do that next to me whilst I'm beachcasting. It also means you can get a Kings when you fancy one & get the shack to cook up your catch for you. I have had difficulty identifying some fish off the beach. Mostly the shack boys know if they're eaters or not but not always the name. Keep the end gear simple, breakaway and a simple one hook rig - use 20 lbs mainline but also a use a shock leader cos you'll need a heavy lead everywhere.
Also if you follow the coast road from coco beach up river towards Verem there's a place called Fort Reiss fishing is ok & you can use lighter tackle, but holdig the bottom is diffiicult.
Tide is very important
And lots of cat fish about, not big wels cat fish like here but little spiky things that go sceptic of you don;t clean the whole they leave in your hand. They seem to live quite happily in freshor salt water.
Taking out a boat rod and a beach caster this year (next year actually but you know what I mean) which I'll be leaving with Sanjay frm Ice & Spice so if you want go fishing andwnat some decent gear to fish with speak to Sanjay -guess what, he has a boat!
P.S. Don't fish in bare feet it's a pain in the butt going to the hospital to have the hook removed.....yes, that was me.