^ That is if you are sure you want to go saltwater, as was mentioned above you have some fw options for aggressive fish as well.
If I may input my $.02 to the OP. MFK is an awesome place to get information for people in this hobbie and to learn from other people's experience, however, there are a lot of very opinionated people who don't have much patience, so it makes it hard to have a discusion like the one you attempted in this thread without getting attacked.
Thanks everyone who took time to read this thread and think about it and contribute with useful advice.
I'm still thinking about the chain catshark, but it appears to be extremly hard if not even impossible to aquire here in Morocco.
The shark was an idea that was supoused to be a b-day gift for my wife since she is in love with sharks
it's not like I came here and said hey guys I have a black tip shark in a 180 gal, what do I feed it?
Personally I doubt that Chain Catsharks will be easy to find - in Europe or Northern Africa - since they are a North American species. Especieally since it's fairly difficult to find them over here.
That said - there are some options. Naturally you will have to check and see what's available in Morocco. But there several species of catsharks in European & Mediterrean waters. Also you may be able to get species from South Africa and Australia, where there's several species of catsharks . Just take your time and do your research on the various species.
With all due respect, you've been here since August. Assuming I'm one of the impatient people you're talking about, that's fair, but I'm perfectly willing to be patient with those that genuinely want to learn. I'm not so much with people that ask questions that could easily be Googled, and refuse to accept reality when it clashes with their desire to plunk a potentially massive fish into the smallest tank they can because it looks cool. This happens frequently here, on other boards and elsewhere in the hobby, and it spits in the face of everything people that work hard to keep these fish and other animals do.