Brown stuff on sand - HELP!

[hachadwick]

Hello everyone!
I have recently switched to a 120 cube and everything is really healthy! The coral are growing like weeds and the fish are always active and healthy. In fact, I have no issues with the exception of one! :frustrat:
Every day, when the lights come on my sand starts to turn brown on the top. When I stir it up, it comes back after less than 1 hour. Lights out, the color goes away. I assume this is some type of algae but I am not sure what kind or how to treat it. I purchased a Phosphate test kit and I am showing a level just barley above zero. I don't have any other kind of algae in the tank though, just this brown dusty stuff.

I have a fuge running but it is very young.

I am using a small grained sand for the bottom which I stir every day. :grumble:
I would like to get it to where I don't have to stir it everyday. Here is a pic of my tank and the brown stuff, of course I have my hood and lights off at the time of the pic.

 

[Reefer69]

Diatoms? Not that big of a prob. Silicates get used up and it be fine.

 

[hachadwick]

ok. I tested my RODI water and it has zero phosphates. So maybe just give it more time?

 

[Greenman]

Im having a MAJOR phosphate issue and green hair algae and I cannot for the life of me figure out what is fueling it. Tank has been up for 5 months, phosphates and nitrates both test 0... im using RODI water... makes me want to punt a puppy...

 

[ErinCahir]

Sounds like diatoms to me. If it's dusty and not stringy, it's diatoms. They'll go away on their own once all the silicates from (what I assume is) new sand gets used up.

 

[hachadwick]

Thank you. Could the food the feeding it be contributing to the problem? I feed frozen cubes, seaweed for the tangs, and sometimes pellets.

 

[hachadwick]

Also, should I increase circulation on the sand bed? My flow goes over the corals and the main water column now.

 

[ErinCahir]

It's ugly, but it's not going to hurt anything. I'd just leave it.

 

[kbuser92]

Also, should I increase circulation on the sand bed? My flow goes over the corals and the main water column now.

It could help, but its not a guarantee. You should, however, adjust them if needed so you don't have dead spots where crap and detritus can collect.

 

[hachadwick]

I don't have anything building up on the sand bed or rocks other than this brown stuff, so I guess I'm going to leave the fans alone. Thanks for all the help everyone. I'll update when something changes.

 

[pkc]

Food always contributes to algae growth as at the end of the nitrogen process you are left with nitrogen, orthophosphate and phosphorus, all encourage algae growth.
Any form of algae based planktonic life, as is phytoplankton to name one, their shells are pure silica, if you add them for food or if they are alive and once they shed or die, you get more silica.
Diatoms don’t just grab water born silica, they settle on the silica as well and the silica that permeates your bed from shells are broken down to be water soluble.
Do you use a form of GFH,it lessons water soluble silica.

 

[hachadwick]

I do not use any GFH but I am going to look into it. Also, does the little bubbles that build in the sand present a problem? Should I be concerned?