Hair Algae on sand

[Der_Iron_Chef]

I'm curious, I don't think anyone has asked about your source water. Do you have an RO/DI unit, or do you buy filtered water, or use tap water, or what? If your phosphate levels read 0 and you're feeding sparingly, there's got to be something feeding the algae.

[likwid]

I am using RO water, and dont have any fish in the tank, so I feed a tiny bit once a week or so. I am very confused.

[geobee]

how often do you do water changes? personally i would remove the sandbed completely, i find its much easier to clean!