You should tell him, and better because if it is something that you like, that you are passionate about, then he must understand it, besides it is about money, of some kind, because he should find out, it is not known if he also wants to try it and also how you have more It is experience because you tell him that you can do how he can do certain things, and you can grow together, so when you plan to play and have money, then he does not get angry, even though I say that you are a free woman in your finances and that you He must be clear about that, but it doesn't matter, because he can later complain to you for any thing and tell you that you have hidden so many other things from him. Believe me, that later causes problems, in case he discovers that you are playing hidden, you can also offer, because he will regret that you do not trust him.
And I can assure you that because when my wife doesn't care about something in particular, she suddenly says that I don't take her into account for the things that she does and no, that's a needless fight, and if you tell her and he doesn't like it, because he has to accept it anyway, because it's your freedom and it's just what you like to do and he must Respect that.