i just noticed this morning while switching everything from my 20l to my 40 that my clown fish have got some black spots on them....i put some new coral in yesterday from my buddies tank cause it had a leak in it...i put a torch coral zoas and green star polyp didnt know if maybe there was a hitch hiker on them or not....he didnt have any fish in his tank at all....if u have any ideas what this could be pls let me know thanks