Green Algae... what is it?

[hei12]

Hello, I am new to this, but I have a question that I hope someone can answer... I attached two pictures. I have a 100 gallon FW tank and this green algae is on the sand, log and walls. I don't know what it is, so I can't get rid of it. Does anyone know what it is and how to make it go away??

 

[jlk]

Hi! I just (kind of) tried to address a similar problem in 'texaspepper''s question about green algae. I think you may have a similar problem. Check out the above thread and see if my answers help. How are your nitrate levels? How often do you change the water and how much do you change (%)? I will try to help but im not an expert on this!

 

[BBradbury]

Green Algae

Hello hei...

Appears to be "Green Algae" to me. This type usually sticks to the walls of your tank, like a kind of film. I believe the term is "unicellular algae".

This type of algae is caused by high levels of phosphate and/or nitrate in the water.

The usual remedy is several, large water changes. Change half the tank water every two to three days and service your filter equipment. Be sure to do a thorough vacuuming of the gravel too, if possible.

A long term remedy is to get more plants into the tank. Faster growers are best, like Water sprite (floated), varieties of Hygrophila, Anacharis, Pennywort, Hornwort, etc.

B

 

[hei12]

I just tested my nitrate levels, and they are coming out at 0 like usual. I do 20-25% PWCs every week, and I have a lot of plants but they stopped growing right about the time this stuff started forming. I just added some algae stuff so I will see if that helps any.

But definitely keep the advice coming Thanks!

 

[jlk]

I would follow BBradbury's advice and go with lots of large water changes. Its the only way to reduce the algaes food source. The algae stuff may cause more problems than its worth and it will only be a temporary fix. Also make sure your not overfeeding and cleaning up any leftover food. Fish food is a big source of phosphates.

 

[Dale_I]

Can you let us know what kind of fish you have? It is unusual to have nitrates at 0 ppm in an established tank. You should have some measurable nitrate unless your plants are so prolific that they are maintaining a 0 ppm nitrate level.

 

[hei12]

Well I tested the nitrates today and the tube was yellow, which means 0. So they are either 0 or really low, which I thought was good....
I have an angel fish, red tailed shark, some zebra danios, 3 barbs, 2 clown loaches, and a few other random fish. Plants are pretty plentiful, just not growing at the moment (not sure why, they used to grow like crazyyyyy).

 

[Deadsea]

You never said unless i mist it, how long has the tank been up and running with fish? Tank cycled?

 

[hei12]

The tank was set up in January... so it has been about 9 months since we started putting things in it. I am taking my water to get tested at PETCO soon, just need to find time to get down there.

 

[aqua_chem]

That algae is known as blue-green algae, actually a type of cyanobacteria. It is cause by, wait for it, low nitrate levels. BGA can fix nitrogen, allowing it to out compete other algae and plants who depend on water soluble nitrogen (ammonia, nitrites, nitrates). The fact that you have it in a tank with 0 ppm nitrate makes it a lovely textbook case.

Ways to kill:

3-4 day blackout OR Erythromyacin (harsher and will need more research into its use)

AND

Add more nitrate. Dry ferts will ultimately be better.