Is this blue green algae

wgoldfarb

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My tank has been set up for almost 2 months. First I added plants but no fish, and it sat with plants only for about a month. I am using EI dosing with great results - good growth, and no algae. Then about 3 weeks ago I added fish. Two days ago I noticed what I think is blue-green algae on the substrate along the front of the tank. I hadn't realized that at this time of year, the angle of the sun early in the morning is just right to come through a window on the second floor and come straight into the front of this tank on the first floor!

I have now blocked the sun, and want to get rid of the algae. Thankfully it is just a few dots here and there at the front of the tank (where the sun was hitting). I will also plant something (either monte carlo or S repens, both of which I have in other parts of the tank) at the front of the tank which may or may not help but at least will look better :)

But before I do anything I wanted to confirm that this is indeed blue-green algae:
bba.jpg


I believe the brown stuff are diatoms, which I expected in the new tank, but I don't know if those green dots are indeed blue-green algae? It is showing nowhere else, only on this strip of sand along the front of the tank, where the sun was hitting the sand directly.

If it is blue-green algae, I've never had to deal with it before. It is so contained that I am thinking of spot treating. Are there any pros or cons of Hydrogen peroxide vs. something like Chemiclean (other than the obvious cost)? I know Excel won't do anything to the BBA... I assume if used properly both are safe for fish (otos, ember tetras and rummy noses).

If it is NOT blue-green algae, what is it? In that case, would spot treating with Excel help? I add Excel daily as part of my EI dosing regime, so I could add the entire dose in this spot with filters off, let it sit for 5-10 minutes before turning the filter back on.

Thanks!
 
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Looks like cyanobacteria to me (blue-green algae)...its not a true algae although it does photosynthesise...which is very annoying and unfortunately makes it difficult to get rid of. It looks like a tiny amount though so if you get a handle on it now you should be good. I recommend just siphoning out the sand that it's growing on and replacing it. If you've sorted your lighting out that may just do the trick but you could also try increasing flow in that area, some say it prefers slow or stagnant water but see what happens 👍 hope that helps!
 
It is, I find it is more typical when starting a new tank, but with reducing lighting and constant removal it starts to disappear.
 
Ok, thanks for the replies. I have eliminated the sunlight that was causing the problem, and will scoop up the affected sand, hopefully that gets it under control.
 

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