Brown tint on Sand in 14 Nano Cube

[ebarth00]

I have been running my tank for a little over two months. I have Two very different looking green star polyps that are are opening regularly and looking awesome.. and a cleanup crew existing of:

3 Astrea snails.
3 Nassarius Snails, Margarita
1 Striped Turbo Snail
2 Bumblebee Snail
6 Blue-legged hermits
Last week I added 2 small clowns

My water results have been coming out fine. However my sand seems to have a brown tint on the top now. The live rock and even the sides of the tank seem to be clear, it is just the sand that is turning brown. I think it might be brown algae but am not sure? Is this just a normal part of the cycling process? Am I doing something wrong? Do I need more Nassarius snails to stir up the substrate? Or maybe more rock instead of just fine marine sand? Please advise if you can. Thanks.

[Phurst]

A pic would help, but it sounds like it's diatoms. They're a normal part of the "algae cycle" in new tanks. It should eventually clear on it's own, but you can get CUC members that will help.

[AlishaMichelle7]

This is a quick discussion on diatom algae in newly established aquariums:

The Real Scoop On Brown Algae Joe Jaworski’s Weblog

The article seems to downplay the notion that silicate can leach out from the sand causing nuisance algae. I don’t know if the guy is right or not but I had problems where I would have large quantities of algae on my sand (and nowhere else in my tank) and my phosphates always tested low so I wouldn’t completely rule out the notion (although there could have been other factors involved as well I suppose).

[CarmieJo]

Diatoms are a fine golden brown covering. They are easiest to see on sand but are probably all over your rocks too. As far as silicates go there is no doubt that diatoms need them. But most everything scientific I have read says that you are as likely to get silicates from silica sand as you are from your aquarium glass. That is to say it just doesn't happen. By the way silica sand is playground sand. The white aragonite sand that is most poplar for aquariums does not contain silica.

[lReef lKeeper]

i agree, it sounds like diatoms.