- Joined
- Oct 12, 2020
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- Location
- Punta Gorda
- What state or country do you live in
- Florida
That isLooks like it could be cyano. You have to use chemiclean right now it’s the only way.
DING DING DING... there you go. I had black sand in my first reef tank. I had the same issue constantly. It drove me insane. I was at a LFS called After the Ocean in Sarasota discussing this with the owner and the Eshopps rep interjected and asked point blank if I had black sand. He said that it is essentially perpetual diatoms. There is something in the black sand, Iron maybe - I forget. They told me to replace the sand. I did. Problem never came back.Dusty and reddish. Hard to be positive on color, black sand bed. It vacuums and comes back.
My tank was the same age as yours....


