What kind of algae is this?

[flavia21]

Hey everyone I have a rock in my tank and it used to have some green agae and now it seems like its dark.

Is this black algae? What do you guys think it is and why?
All advice is welcome! Thanks!!!

 

[Elkairos]

You should definitely detail the amount of light and time you allow for it... As well as tank specifications..

 

[flavia21]

You should definitely detail the amount of light and time you allow for it... As well as tank specifications..

I have a 15gal tank and I usually have the likes on for 6-8 hours a day. I have a Platy, 2 neon tetras 2 guppies and 6 guppy fry.

 

[Elkairos]

Well, I don't mean to put you on the spot, but my mother insisted on keeping her hybrid cichlids. The fry have been growing in a ten gallon which she never cleans unless I visit. As you know, fry eat a lot and therefore digest food quickly. The tank water is not great and gets about 7 hrs of light each day and has plenty of blackish spots on decor... How often do you do water changes? That might be a problem.. Watts?

 

[flavia21]

Well, I don't mean to put you on the spot, but my mother insisted on keeping her hybrid cichlids. The fry have been growing in a ten gallon which she never cleans unless I visit. As you know, fry eat a lot and therefore digest food quickly. The tank water is not great and gets about 7 hrs of light each day and has plenty of blackish spots on decor... How often do you do water changes? That might be a problem.. Watts?

I had the fry in a fish net but they've become big enough where they don't get eaten anymore ( they're an inch or so). I change the water once a week or so.

 

[Elkairos]

Well, the algae is ugly.. Try scrubbing it off the rock in a bucket with tank water.. Dark algae like that eventually gets hairy and stays dark/ brown

 

[Jweickum]

Brown algae is caused by low light levels, low oxygen, and high nitrate levels.

So regular partial water changes.
Get a higher watt lighting.
Get a pleco or otocinclus.
Or put plants in to fight the algae for nutrients.

 

[Rivercats]

If it's fuzzy then you have Black Beard Algae. Only run your lights 6 hours but we need some info on the tank. Is it planted? Do you know you nitrate and phosphate levels? Also how often do you do WC's and how much to you change out each time.

Low light does not cause algae and neither Pleco's or Oto's eat BBA. You can remove your ornament/rock from the tank, put some papertowels in a sink and put the ornament on them then pour Hydrogen Peroxide 3% over it. Then wrap the wet papertowels over it and let it sit for 20 minutes. Then you can just put it back in the tank, no rinsing. The BBA will start changing color red/pink/white within 24 hours which means it dying. BUT unless you correct the problem causing the BBA it will continue to come back.

 

[Guppies]

Looks to me to be black bird algae ?

 

[Fresh2o]

Looks to me to be black bird algae ?

Ka-kaw! (I couldn't resist)

We know you meant "beard"