Hmmm, I must break ranks with my friends above, because "I have been liking seafood since I first tried it" sounds perfectly natural to me, albeit colloquial. In this context, "liking" means "enjoying," and it is very common to use it in that sense.
How are you liking your new job?
Is she liking being married?
When I read the sentence in question, it tells me that the person has been eating a lot of seafood since first trying it, and has enjoyed it.
e.s.s., this is a translation forum, and the rules require you to provide the source text, which is Spanish in this case. That way, we can know what you are trying to express, and help you say it in natural English.