Black spots on my fish?

Sick? New black spots on some fish?

• I have 3 tanks one 40Gal Gourami tank one 75Gal Shoaling tank with multiple breeds and a 110Gal Cichlid tank thats in the process of being cycled. I just recently did an overhaul of my 75Gal tank. Filtration, heating, air, substrate ect. Water pH is perfect 0clorine low to no amonia. But i've noticed that a feed spieces have developed small black spots on there underbelly there still moving around fine and shoaling, eating. There are no visable signs of disstress or sickness but I just want to make sure there's nothing wrong. If there is I need to know right away so I can remove and quarintine the fish before the others contract what they have if anything. Can't find really anything in books or from websites. So if anyone has any suggestions or idea of what they are then please feel free to post. (As always experianced fishkeeps only please) Don't appriciate newbies to the trade posting comments and have no idea what there talking about. Thanks

• Answer:

  I once had an issue with African cichlids developing black spots on them. Despite the best efforts of some friends who were extremely experienced (breeders and importers), the best guess we came up with was some kind of bacterial infection that caused black pigmentation. Apart from that, they were completely healthy, bred normal healthy babies and lived long healthy lives...just with black spots! Apart from euthanizing one and getting it autopsied by a suitable laboratory (forget a vet, nowhere near enough specialized), very expensive though, there's not much you can do other than euthanizing all the fish, throwing out all the gravel etc, and thoroughly sterilizing the tank. If they're all otherwise healthy, I would just accept them as having extra personality lol. Sorry cant be more help but there are some very rare and difficult to diagnose diseases out there. Good luck :D