What's on my Live Rock?

[newsalt]

I've attached a picture of some brown/rusty growth on my LR. Can someone identify it? Is is diatoms? Will it go away on it's own. Today's water readings: Ammonia - 0, Nitrite - 0, Nitrate - 20, pH - 8.1, SG - 1.0223.

Thanks.

[reefrunner69]

Yep that is diatoms!!

Looks like your ready to add a clean up crew. I'd start with an assortment of nassarius, trochus, nerites and cerrith snails. They should clean it up in a couple of days to a week and keep it clean. Just make sure not to get too many, or your tank may not provide enough alge to sustain them all. The diatoms will slow down on their own, once the silicates are used up in the water, but won't completely stop.