Diatoms or Algae?

Had a rough start with my tank, but its slowly getting better. I've had this brown stuff on for maybe 2 months.

 

It looks like diatoms to me. How long has your tank been running?

 

Is it on your sand as well? I would say diatoms also, im guessing your tank is about 4-5 months old?

 

A bit on my sand but my goby nails that. Heres more background on what happened on the tank.
My Reef Tank started with a disaster - Reefers Anonymous

 

i have the same stuff on the back wall of my tank -- my tank has been running for about 6months, diatoms or algae?

 

They are Diatoms from Phosphates in the water you are using I see that you used a water conditioner to condition (tap water) i assume?

 

ya and of course like a newb I started the tank with tap water :-[

 

Diatoms are very common in new tanks and also can appear in older tanks where you add new equipment as well, or if you use tap water, also can get it from some prepared foods. Diatoms feed off silicates and phospates feed them also Hope this helps

 

Thats okay are you using RO/Di water now? Tap water is the source of your diatom issue. If so it will take a while but eventually they will all go away. I actually started my first tank with tap water also about 4 months in the diatoms were out of control everything was covered and it looked like a blanket on my sand bed.

 

For reference, my diatoms started on week 4. They lasted for all most 5 weeks and it was everywhere. Then the red slime algae came, now its gone but replaced by green hair algae lol.