Algea ID plz

[Salty Bginners]

http://reefcentral.com/gallery/data/500/125597algea.JPG
Amonia-0
PH-8.2
Nitrate-0
Nitrite-0

I do bi-weekly 15% water changes with RO/DI water.
I have had this problem for a long time and didnt know it waz a problem till someone told me it was. I scrub the stuff off of the rocks with a toothbrush thenb rince it on RO/DI water but it keeps comming back. Can anyone ID this and tell me how to get rid of it?

[Salty Bginners]

Is this not the right forum 4 this?

[graveyardworm]

Looks like some sort of green turf algae. What do you have for a cleanup crew?

[kmk2307]

Maybe Derbesia or Cladophora. Either way, lower nitrogen input or increase nitrogen export with a competing alga like caulerpa or chaetomorpha. Do you have a skimmer? Do you test phosphates? Make sure your RO water is actually pure by testing the phosphates or with a TDS meter. A LFS might be able to test your RO water TDS for you.

HTH,
Kevin

[Plantbrain]

Looks like Cladophoropsis,

Regards,
Tom Barr

[Salty Bginners]

turbo snails and hermits and a cucumber as cleanup
no way to test phospates
yes i have a skimmer
whats a nitrogen
are the competing algeas good?