What is this purple stuff under the sand?

[Optional (AKA Mike S)]

Hello. I have an 80 gallon tank, had it for about 5 months. I have CC and here are the lights i have:
4 PC's 65wts each 2 of them are actinic(20000k) and 2 are day lights(1000k). I have been noticing that some sort of purple stuff is growing under the CC. They are all at the same level. They are all 1 inch under the sand in a line. It is light purple. What is this? Is it good? Thanks for your reply.

 

[Anonymous]

More than likely either cyano bacteria or coralline algae.

 

[danmhippo]

1" under the sand, same level? It may also be a sign of anaerobic bacteria activities.

 

[Morg591]

If your tank is a glass tank you could have coraline algae that deep on the glass. The sides of a glass tank can send light that deep just like a fiber optic cable.

 

[Optional (AKA Mike S)]

So, is this stuff good? Does this mean good water quality? Thanks for all your replys here.

 

[karlas]

its the formatiom of your dentirifing levels of the dsb heres a site that can explain whats going on under there
http://atlantisaquatic.com/dsb.html[/code]

 

[whusband]

If your tank is a glass tank you could have coraline algae that deep on the glass. The sides of a glass tank can send light that deep just like a fiber optic cable.

corraline doesn't necessarily require a lot of light to grow. it can be found on live rock 100's of feet down in the ocean

 

[karlas]

there are actually many colors of corraline alge that grow in different levels of light. purples, pinks, yellow, green, blue plus other colors i have heard of

 

[Optional (AKA Mike S)]

I've been looking at some of the sites discribed, and now it is turning a bit green, and some brown. Just thought i would tell you that. It is quet beautiful turning different colours every other day or so...
And karlas, i don't have a DSB. I have CC and some organic stuff(almost loke LS) from my cucumbers and bristle worms and such. Here are all the levels:
top sand-brown and some purple
middle-purple, most brown
lower middle-all purple
bottom-blue/nothing
Again, i dont have a dsb, just CC. I have heard of colors changing in a dsb, but never CC. Thanks for all your help here! Dont care why it is growing, just care about what it is and is it good. THANX!

 

[karlas]

Optional (AKA Mike S) sorry i guessed i missed the cc part. but if your getting other colors thats pretty cool. on my rock i have had purples, pinks, green, burgandy and spots of blue. the green and blue is dissapearing though the purple is taking over. heres a site with good pics of what some of them look like also i have heard of corraline covering cc sometimes maby your one of the lucky ones
http://www.saltreef.com/galleries/coralline.htm

 

[Anemone]

I'd put my vote in for cyano as well. Just a normal part of the nutrient cycling that occurs in DSBs (and CC beds as well).

It could also be coralline - the easiest way to tell would be to run a finger along it. If it's slimey and comes off easily, it's cyano. If it's hard and doesn't come off, it's coralline.

Kevin