Algae Is Taking Over Tank

[Inchworm]

Over the last few months I've been watching this 55 gallon tank get overgrown with stringy green algae. Watching it grow has been both fascinating and horrifying. I've never seen anything grow quite like this before.

Underneath that mess there is a lovely piece of wood that used to have java moss thriving on it. On the other side of the tank are three big moss balls which are now covered with the stuff. When it started out it was pretty but now it is running amok in there.

A few days ago I noticed that one of my swordtails did not come up to the top to eat. When I investigated I found that he was trapped inside it. Fortunately I was able to get him out but have decided it's time to do something about the situation before others get caught in it as well.

This tank gets more natural light than any of my others. At this time of the year the sun is directly shining on it for a little while in the morning before it rises higher in the sky. Is that the cause? It didn't do anything like that last year.

Normally I consider myself lucky to keep java moss, java ferns, and anubias alive in my tanks. Seeing some green in there was fun while it lasted but now it's time to get this tank back to normal. Can this be done without stripping the tank and starting from scratch?

Your advice will be greatly appreciated.

 

[cheesy feet]

Hair algae is highly attributed to high light levels; similar to pond blanket weed that thrives in the summer...Stick a background on the back to prevent most the light coming through - it should reduce its growth a lot.
It looks like 1/3 of it could be removed by hand anyway.
You can buy products that kill hair algae, the trouble is the nutrients left behind leave plenty for new algae to regrow.
Planting the tank densely after doing this could out-compete the hair algae for nutrients too...The only tanks I have ever had hair algae in are high light one's with a lack of plants.

 

[erk628]

Just scoop out what you can with your hands then suck the rest up. A magnet will get the glass clean!

 

[Dave Spencer]

You appear to have Spirogyra. In my planted tanks, I have used it as an indicator of poor CO2. I would be surprised if this was the underlying cause in a tank as lightly planted as yours, so I would personally look at the direct sunlight as being the origin of the cause.

As you probably have experienced, removing it manually is a losing battle, as it grows so prolifically. In your case, I would definitely remove the wood infested with it, and boil it. At the same time, manually remove as much of the rest as you can, including binning the moss balls. Carry out as big a water change as you can, then put the tank straight in to a three day black out.

Once the black out is over, carry out another huge water change. You may well notice some Spirogyra persists. If this is the case, and it appears to thrive once again, do not hesitate to repeat the above steps.

Spirogyra can be very tenacious, particularly when it is as well established as yours. Black outs are just about the most potent weapon we have to get rid of infestations, especially when they are used in a series of two or three on established blooms where they are just about the only successful method.

If the direct sunlight does turn out to be the source of your problem, you are going to have to address it, as the Spirogyra will constantly reappear.

Dave.