Brown algae near the surface

[scottward]

Hi Guys,

I've noticed a bit of brown algae growing on leaves toward the surface of my tank. This brown algae wipes off easily and I'm not too worried about it, more curious really.

I always thought that brown algae was a syptom of insufficent light, usually around the substrate level.

The plant leaves are getting a decent wake of light near the top of the tank, and there is none of this brown algae down any lower.

Due to the hot weather here is Brisbane at the moment, and I don't have a chiller, CO2 levels haven't been able to be optimum, so I think I can attribute that to the presence of the algae. The colour has me a bit stumped though? Why brown and not green?

Scott.

 

[shoggoth43]

Most likely these are diatoms? The wipes off easily part is what leads me to that conclusion. What kind of circulation do you have near the top of your tank?
-
S

 

[scottward]

Hmmm. Possibly the circulation near the surface is not too good, as I only have a single cheapie powerhead working more the lower depths.

Would a good prop pump as we've been discussing in another thread help me out here?

So you think this algae is really just a 'normal' thing occurring simply due to poorer circulation in this area?

Come to think of it, I do get worse BBA near the top of the tank, where my water inlets are. I suppose the circulation near the top might be a bit lousy?

Scott.