Tank has been running for 2yrs. I have had some hard sand in some small areas for about 14mo and in the last 3-4mos it has gotten worse. Sand bed is shallow ( 1-1.5" ). I had Dino's for about 3mo and they have been completely eradicated for the last month or so. My eradication consisted of adding more pods, dosing phyto, MB7 and MB clean alternating between the two and adding silicate to induce a Diatom bloom. I also allowed my nutrients to increase to NO3 of 19ppm and PO4 to 0.26ppm. Tank is Dino and Diatom free so I decided to remove a portion of the hard sand. The green substance on the sand is not slimy and will not rub off. I stirred up some sand in some saltwater and could not find any organism under a scope. It is actually hard and looks like coralline algae. I put the hard sand in a container and added some hot water with some vinegar ( 70/30 ratio ) and it started to bubble up instantly and made a fizzing sound.
My tank nutrients and chemistry as of today: NO3=7.9ppm
PO4=0.12ppm ( still high but coming down slowly )
Alk=9.1
Cal=450
Mag=1510
ALK, Cal and Mag have been consistent since day one of tank setup. I match my salt mix parameters. ALK and Cal are dosed in equal amounts 8 times a day and dosed 1/2hr apart from each other with CAL being dosed first.
So, is this Calcified Sand or maybe bacteria secreting Glycocalyx?
Why did the sand bubble up when vinegar was added?
What could the green substance on the sand be besides Coralline Algae? Again, green on the sand is not slimy and will not rub off. It is stuck to the hard sand.
My tank nutrients and chemistry as of today: NO3=7.9ppm
PO4=0.12ppm ( still high but coming down slowly )
Alk=9.1
Cal=450
Mag=1510
ALK, Cal and Mag have been consistent since day one of tank setup. I match my salt mix parameters. ALK and Cal are dosed in equal amounts 8 times a day and dosed 1/2hr apart from each other with CAL being dosed first.
So, is this Calcified Sand or maybe bacteria secreting Glycocalyx?
Why did the sand bubble up when vinegar was added?
What could the green substance on the sand be besides Coralline Algae? Again, green on the sand is not slimy and will not rub off. It is stuck to the hard sand.