in jubelive city go to the left the you will come in a small building talk with the fisher he will give you an old rod to get the good rod you have to be under soleceon town there is another fisher talk to him and you Will get a good rod to get a super rod go to the battle frontier with the ship go up (after national Dex XD) and talk to the fisher you will get the super rod
it was in route 218 in platinum,diamond and pearl ask the second dude behind the trees
Pokemon 80 is Barboach. Try fishing for it around Jubilife City on Route 203 or on Route 205 near Eterna City.
you can only get one fishing rod. you get it from collin's dad in the begining. (but i forgot how. honestly sorry!) you can go lure fishing at the fishing hole too.
Heatran is a ledgendary in Pokemon platinum.
its a magikarp lvl 60 or over i caught a lvl 80 magikarp with one dive ball you catch magikarp in the water under the guys pool not the pool but the water you can surf and use fishing rods (i would recommend a super rod)
canalave city
you get the fishing rods from fishermen.
Around kanto certain fisherman give you fishing rods.
Talk to the Fishing Guru.
Fishing pole? You use a Super Rod to catch it. There is no fishing poles Pokemon,only Old Rods,Good rods, and of course Super Rods.
Maybe its the environment or its because your rods is weak
You have to surf with one of your Pokemon or go fishing with one of the three rods.
in lots of places. lol
I know that you get the super rod in Route 12.
Fishing in Mt. Coronet
By fishing on Route 220.
use different fishing rods and try items that make pokemon come near you