My 180g FOWLR tank that is about 4-1/2 yrs old. Over the past few months, I've noticed that the top layer of my sandbed is turning a bright green. It's not a mat like cyano, and it's not hairy because I've dealt with that too. It's like the individual grains of the sand are green. I can't figure out what it is. When the light are out at night, it seems to go away but as soon as the lights come on, it turns green again. I use three AI Sol Blue LEDs over the tank. I use IO salt. The one thing I'm thinking is maybe my RO water isn't great. It's been a while since I changed the cartridges and the Spectrapure Silica Buster cartridges. I just ordered them and will replace them ASAP. Other than that, the water is clear and the fish seem fine.
Anyone else experience this?
Thanks
Anyone else experience this?
Thanks