Algae question

[isubrian]

Recently my 10 gallon SAP tank developed some dark brown or black algae on the leaves of my live plants. It comes off fairly easily by rubbing the leaves between my fingers, and is thick enough that it usually keeps the shape of the leaf that it came off of. It is not the hairy type of algae, but is almost like it was painted on the leaves. Once the algae was rubbed off, the leaves underneath were nice and green. I will post pics and water parameters after I get off work, but thought I'd see if anyone has had a similar experience and could tell me what to do to get rid of it, and what might have caused it.

Thanks!

 

[CFC]

That sounds like a cynobacteria infestation rather than an algea bloom.

I'll move this to the planted tank section where you are likely to get more help.

 

[isubrian]

I checked the water parameters tonight and they look pretty good...nitrate 20, nitrite 0, hardness 200. The picture isn't the best, but here is kind of what the plants look like with the black stuff on their leaves:

Does anybody have any ideas what is on the leaves, or how I can get rid of it?

 

[iggy01]

To be honest I'm not sure exactly what that is. Cyanobacteria comes in many different colours, including browns and blacks, but I haven't actually seen those forms.
Does the algae smell really bad if you get some on your fingers and sniff it? Kind of like a swamp smell?

How long has the tank been set up?

How much lighting do you have and how long is it on for?

Sorry for all the questions!

 

[George Farmer]

I'm stumped on that one - never seen anything like it. Sorry. Answers Iggy's questions and hopefully we can help out a little more.

 

[isubrian]

I smelled the algae, and it doesn't have any smell. I removed the algae from a leaf on my moneywort plant, and the part that came off was almost exactly like the leaf itself...it had the same shape, and was nearly the same thickness. I was able to roll it into a ball between my fingers. The tank has been set up for approximately one month. I have a 15 watt "plant" bulb that is on for 12 hours per day. Thanks for helping me out!

Here is a picture of the algae on my moneywort. As I said in an earlier post, the algae easily slides off of the leaf and stays in one piece. The leaf under the algae is nice and green.

 

[zig]

If it is cyanobacteria poor water circulation can often trigger it.

 

[iggy01]

New tanks are prone to diatoms which looks like a brown algae. It usually goes away after a few weeks. It is often said to be caused by excess silicates in the water or low lighting. I'm not 100% certain that's what you've got, I've never heard of it peeling off plants in the way you suggest. Although it does usually come off easily.

When you clean it off the plants how long does it take to reappear? Are we talking hours or days?

 

[isubrian]

It has been a few days since I cleaned off a few of the leaves and hasn't come back yet. I'll have to try cleaning off the rest of them, and see if it comes back.

 

[iggy01]

I think you can rule out cyanobacteria then. It usually reappears very quickly, usually within a matter of hours.

 

[isubrian]

One other thing I thought of...

The substrate is sand (sandblasting sand to be exact), and when I do water changes, it gets churned up a bit, and often settles on the leaves of the plants. Is it possible that those grains irritate the leaves in some way, causing the layer of what I thought was algae, to form?

 

[iggy01]

I doubt it. But you never know, stranger things have happened!

That's the thing about this hobby. Just when you think you have it figured out, something happens that totally surprises you.

Did you clean it off the rest of your plants?

 

[isubrian]

I have cleaned it off of most of them, but still have a few left to clean. Things have been really busy lately... I'll let you know if it comes back after I get them all cleaned. Thanks for your help!