I have a dwarf pygmy anglefish, and I love him to death! he's only ever nipped at the very hardy corals I have, and it wasn't aggressive at all! The only thing about him is, there is close to no information out there for this little guy! He's a great addition to a larger nano tank, and not a lot of people know about him. Do any of you have one or have had experience with one? Would love to hear stories/ advise!