# White Spots on walls of Sump



## robert220

Hello all. I have a 220 fish only salt water tank.
I have a euro fil 240 sump with a asm g3 skimmer
I noticed today that there are white spots approximatly .5 inch round inside the sump only? what is it? do i need to clean? PH 8.3 nitrate is approximately 20ppm 0 nitrate and 0 amonia...

please help


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## Cody

Are they somewhat spiral-ly? And are they located where the area is somewhat darker?

And do they resemble this?









If so, they are Spirorbis. They are a filter feeder, and a sign your tank is doing well.


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## robert220

no spiral to them i will try to get pictures. White substance circular, small mound, some have a small crater inside. additional info tank is 9 months old, i keep minimal light in the sump area otherwise algae grows too much on my lines. ( any advise would be appreciated). 
i keep the salt mix at 1.020. temp 78.


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## SKAustin

robert220 said:


> i keep the salt mix at 1.020. temp 78.


Off the subject, but you may want to get The Specific Gravity up a bit. Natural Seawater is 35 ppt (or 1.0264). YOu should strive to a number closer to that for reef, slightly lower (1.023 - 1.025) for Fish-Only systems.


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