Ahh true so true.
If I was to do it again, I'd probably not have any Tangs in my 100g tank. I love them, they are beautiful species all of them. Maybe in a 700g I'd have a few but my reasoning is either reef it, or fish it. In the past I've read most reefs kept smaller fish, nibblers and less aggressive and less pooping fish. Most reefers have tanks 100g and under, I haven't seen any of these actually with enough room to accommodate a fish of these adult sizes. They actually grow pretty fast as I've noticed. I have a Sailfin & Hippo, both are growing fast, & eventually in my 5ft tank, they will out grow it fast as being over crowded something will eventually happen. The sailfin isn't scared to spread his wings and take control. The Hippo is the protector of the smaller fish inside, he will make the aggressor(sixline) back away from the fire fish. I will eventually reevaluate the fish proportions and remove the two tangs, maybe opt for a smaller species at a later date. If I was not keeping corals this would all be different, I'd probably have less rocks, no corals & as much swim room as I could make. One day I would like to build a larger system, thinking display 300g of the sorts, & a 300g sump, then maybe I'll rethink the tang idea. So in short I think with experience, I would not keep tangs in general in tanks smaller than 200/300g or larger.
