Over the past month I have been getting this black stuff poping up in a few places in my tank. Can someone help me out with what it is? My PH is low as I added abunch of SPS a month ago, but other than that all water parameters are good. Flows the same too. Anyidea on how to get rid of it withoout removing and toothbrushing? will it hurt to brucsh it off inside the tank then vacume the pieces out? or will this spread it? Thanks in advance.