White Fuzz on coraline?

[Sceadu]

Well let me start by giving tank params 75g aga bare bottom with cutting board, 30g breeger sump. 2500g flow per hr, ph-8.1 cal-388 alk-1.9. Mixed sps and softies. Ok so in the past week or so I have seen this white fuzzy stuff growing from the coraline on the bottom of the tank and a little on the over flow. Most of the back glass is covered with coraline and has none of this stuff on it. Now I can rub this stuff off but in less then a day its back. Sorta looks like mold fuzz you see on food. I do not over feed and do a 10 gal water change weekly. This tank has been up and running for a little over a year now.

Anyone have any idea what this fuzzy stuff is?

 

[Sceadu]

NO ONE HAS ANY IDEA?

 

[aqualine]

It could be sponge decay or simply die off, is the live rock new?

 

[mr pink floyd]

pics?

 

[Sceadu]

Its not on the rocks..only on the coraline on the front bottom and the overflow. I heve coralin all over the tank, rocks ect but this stuff only seems to be on the plastic and the starboard. here is a pic...