- Hi I'm new the board and the saltwater world. I've always been a
fish hobbyist but only aggressive freshwater fish (currently have a
155 gal bow w/ 8 piranahs). I just purchased a 210 gallon to put
into our wall and agreed with my wife we could use it as a saltwater
tank but only if we could have aggressive fish inside the tank. So
now I'm looking for suggestions and why those fish. I've heard about
some aggressive sharks any and all suggestions welcome thanks.