ID, pls - voodoo green stuff (w/ pics)

[velfamily]

i have this bizarre green stuff taking over my tank.
it appears to be 'velvet-y'. does not feel slimy and has no hair. it's hard and does not come off. if i rub/scrape it, whatever this is, it seems to be absorbed.

parameters:
nitrates a bit high at 20
nitrite 0
alkalinity 300
ph 8.2

a friend (with years of sw experience) thought perhaps adding more movement in the tank. so we added a small powerhead and this stuff is very very happy we did. it has gotten much much brighter and is seeming to spread faster
march 6th
<a href="http://www.flickr.com/photos/29056768@N00/3367791243/" title="tank 010 by EweDevil, on Flickr"><img src="http://farm4.static.flickr.com/3618/3367791243_ebccabc26b_o.jpg" width="448" height="336" alt="tank 010" /></a>
march 19th
<a href="http://www.flickr.com/photos/29056768@N00/3367791285/" title="tank 040 by EweDevil, on Flickr"><img src="http://farm4.static.flickr.com/3469/3367791285_9b2e45f523_o.jpg" width="336" height="448" alt="tank 040" /></a>


depending on what it is about to cover, determines how it spreads. weird, i know.
see, on LR, it start in teeny tiny little dots and spreads out.
<a href="http://www.flickr.com/photos/29056768@N00/3368615102/" title="tank 023 by EweDevil, on Flickr"><img src="http://farm4.static.flickr.com/3632/3368615102_c9f67e1b81_o.jpg" width="448" height="336" alt="tank 023" /></a>

on shells, it appears to "move in" causing the actual shell to turn a beautiful teal before eventually being coated in the grass-green, 'velvety" stuff. that, doesn't actually feel velvet, just looks that way.
<a href="http://www.flickr.com/photos/29056768@N00/3367791367/" title="tank 0371 by EweDevil, on Flickr"><img src="http://farm4.static.flickr.com/3051/3367791367_6b0d01d0fd_o.jpg" width="382" height="336" alt="tank 0371" /></a>

closeups of a shell i pulled out to show you how it is being absorbed:
<a href="http://www.flickr.com/photos/29056768@N00/3368615240/" title="tank 380 by EweDevil, on Flickr"><img src="http://farm4.static.flickr.com/3575/3368615240_d690de6be6_o.jpg" width="448" height="336" alt="tank 380" /></a>

when you take it out of the water and let it dry, it turns a dull, grey-green.
also, it doesn't coat the bottom of stuff

 

[Sugar Magnolia]

Could be just film algae. What's your phosphate reading? Are you running any GFO?

 

[velfamily]

sorry.... GFO ???? (unsuccessfully, quickly looked for acronym explanations)

unsure on the phosphate answer, too... sorry.....
guess i'll run to the lfs and get a test for it?

 

[Sugar Magnolia]

Yeah, you'll need to keep a phosphate test kit on hand.

GFO = granular ferric oxide. Phosphate removing media. I use Phosban in my canister. Some people use a Phosban reactor which is a bit better.

 

[chris4869]

It's just algae. Your tank must be doing well. It's normal to have them covering up <B>all</B> the rocks exposed to the light. I think they look rather nice with the red, pink, and purple coraline algae.

 

[VacavilleFC3S]

i agree with magnolia it's some sort of algae, i'd start running a phosphate reactor asap and test your water supply

 

[cdbias2]

Perfectly normal for a new tank.
You could reduce your photoperiod a bit.

 

[pb4ugoout]

My tank is about 5-6 months old. When I first set it up I had that stuff covering everything. Rock in your tank will change color over time and thats just part of the process in my opinion. It didn't hurt my tank at all. I added a few pieces of white live rock about 2-3 weeks ago. It's starting to grow that stuff too. I wouldn't worry about it

 

[CoRPS]

I don't really believe in those phosphate test kits. When I had a tank full of all different kinds of algae my phos in the tank and the topoff water and water change water always came back at zero.

 

[Fishboy9227]

That may be because the algae is using up the phosphates so it is not showing up on the test.

 

[CFranklin25]

new rock usually gets green surface algae before it is outgrown by coraline. Think of it as a precursor to coraline algae.

 

[CoRPS]

<a href=showthread.php?s=&postid=14650900#post14650900 target=_blank>Originally posted</a> by Fishboy9227
That may be because the algae is using up the phosphates so it is not showing up on the test.

I know, but then what's the point of the test when A) If you have no algae and have no phosphates it says zero -or- B) You have algae and thus your test kit comes back at zero.

 

[david335]

It could be a new green coraline algae. I have some on my rocks but still wonder what it was.