Black Cyano?

[ezcompany]

I have a black film like thing on a part of my sandbed and i ABHOR it. i sucked it out last night but it came RIGHT back (less than 24 hours), whats the best way to remove it?

nitrate: 7.5

 

[edwing206]

try to lower your nitrates to 0 if possible and try to get more flow over that area and maybe add a conch

 

[SurfOnH20]

I had something similar to what you have but it was more of a reddish gray. My nitrates were at acceptable levels. I found out my alk went down to 6.0. after bringing it up to around 9.5 it went away. See what you alk is and maybe that might be it. Who knows, but it corrected mine.

 

[ezcompany]

wow you were dead right....my alk was at DKH 6.0 as well....slowly increasing my alk supplement (b-ionic) to bring it up to 9.0....whats weird is that my Calcium levels are normal....!!!
thanks SurfOnH20!