One more thing... White spots... Are they calcium deposits?

[dansd]

I've been seeing these white spots for a while now. They appear very hard and can be scraped off the sides of my tank. I first noticed them inside of an old giant clam shell that came with my live rock. Now they're appearing everywhere. I'm guessing that they are calcium deposits, but I'm usually wrong when I guess. My calcium has been holding steady at 400. Should I be worrked? If so, what should I change to prevent them.

Thanks for your help.
Dan

 

[Oceans Ferevh]

Looks like coraline algae to me. It uses calcium to build its structures.

 

[SnowManSnow]

That is coraline algae.. let it go and it will turn light purple in a month or so and spread around Its good algae, in case you aren't aware.. It will help eat the nutrients out of the water so that the bad stuff can't survive.

B.

 

[Anonymous]

If they have little colored (usually purple/red colored) dots right in the center then it isn't coraline algae Its a type of (insert scientific name that I can't recall here)

 

[Mihai]

Man, those are snail eggs. Nerite eggs if I'm not mistaken.
Mihai