I've only been 7 Seas Fishing that one time when Dedric showed me how. I haven't done it again mostly because I haven't had time. But one thing that did hold me back was the problem of what to do with all the fish (not to mention sea horses, sea urchins etc.) that start filling up your inventory.
Luckily for me Ahuva pointed out that you can release them inworld. So I added a fish pond to my front yard. And yes those are tiny little ufo's flying over the fish. :)