Yes, the idea is to go out on a boat where the sea is deeper. That is why they call it "deep sea fishing." The ocean is usually more shallow closer to the shore and if you fish from the beach it is usually called surf casting or surf fishing or beach fishing.
Davey's Locker in Los Angeles is only place where you can go deep sea fishing. There website is as follows: www.daveyslocker.com/deep-sea-fishing/los-angeles/
Well, I've been looking for the fish, too. I still haven't found it. But, you may be able to catch it by going deep sea fishing with Hank, if you haven't done so yet. To go deep sea fishing with Hank, just talk to him until he offers to go with you. [[you can definitely get the mahi mahi deep sea fishing. I've caught it at noon and in the evening. mostly evening time.]]
summer
http://www.allthesea.com/Deep-Sea-Fish.html go to this website it has lots of info on deep sea fish
If you go on a fishing party, the first person to catch a fish will have good luck. If you go to a pond and make the water real muddy, the fish will all come to the top. If you talk while fishing, the fish will hear you and not bite. If you want to catch a two or three pound fish, always use a grasshopper for bait.
Craft a fishing rod and go to water at least 2 blocks deep. You will get fish after a while.
not usually due to how cold it is the deeper you go. the movement of deep sea fish are usually slow and intricate.
the game tries to relate somewhat to real life. you wouldn't try to fish underwater in real life, therefore, you can't do it in pokemon black.
If you go to the sunshine shores cave, click near the base of the palm tree, it should take you there. Also, that's where you can play deep sea fishing. which isn't even that great, only like regular fishing but with bigger fish!
There isn't really fishing around or in Costa Rica but there is fishing trips that go out for a day or two. They go out in the deep waters and have good sized fish.
Finding a good fishing charter to go fishing is one of the best ways to go deep sea fishing if you don't own a boat yourself. But if you are paticular to take your own equipment you can do that as well. However, along with the rod and reel and the lures there are a few more things that you will need to take with you to ensure that you have a comfortable day at the sea. See the related link for a quick checklist that you can refer to every time you go fishing.