Stringy green algae explosion

[Nz C]

hi, my tank’s been running for about 6 months. All good, no problems, levels all fine and obviously fully cycled. All the fish were very happy, no deaths, no algae. Weekly water changes. The last month I have unfortunately only been able to do 2 water changes , one each fortnight.
All of a sudden about 10 days ago this stringy green algae started to appear. It has got completely out of control. It is covering everything and growing by the hour. I’ve cut heaps of plant out but it grows back too fast.

I’ve cut the light hours down and increased the water changes. At the weekend I did a massive water change 80%, and this morning 40%. I have turned the lights off completely today and put a thick blanket over it but I would say it’s slightly worse now than 10 hours ago when I turned the lights off.
What can I do? I’ve been told no fish eats this type of algae - is that right?
Can I add anything to the tank to get rid of it? Is it harmful to the fish?

 

[Colin_T]

Can you post a picture of the algae in question?

 

[The Lumpfish Guy]

levels all fine and obviously fully cycled.

Do you test your own water or do you take it to a LFS?

What were you last readings?

 

[Nz C]

It won’t let me upload a photo as it’s too large. I can’t see a way of compressing or reducing it.

I was using co2 (seachem flourish excel) til recently which I believe also has an algacide in it. But I saw comments on here that it’s not that healthy for fish health, so stopped using it. Maybe I should continue with that.

 

[Nz C]

Yes I test my own water, am 0, nitrites 0, narrates 5, ph 7.2

 

[Byron]

It won’t let me upload a photo as it’s too large. I can’t see a way of compressing or reducing it.

I was using co2 (seachem flourish excel) til recently which I believe also has an algacide in it. But I saw comments on here that it’s not that healthy for fish health, so stopped using it. Maybe I should continue with that.

On your PC you have a program that will reduce photo size. Save the reduced photo and you should be able to post it.

 

[Nz C]

Unfortunately Im working on my iPad so can’t see a way of doing that.

 

[Colin_T]

Set the camera's resolution to 2MB or something low and take more pictures. The images will be smaller and should fit. If they don't then post them on an image hosting website and copy and paste the link here. We can use the link to view the image at the other website.

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It's highly unlikely they would put an algaecide in Seachem Flourish Excel. It would be counter productive to put an algaecide in a plant fertiliser. Plants and algae are virtually the same so anything that kills algae, will usually kill plants. Algae being single celled plants, whereas the bigger plants in aquariums are multi celled plants.

Unless the tank is heavily planted and gets lots of fertiliser and light, there is no need to add carbon in any form (CO2 injection or Seachem Flourish Excel). There is ample carbon dioxide (CO2) in the atmosphere that gets into the aquarium water, and the fish and filter bacteria produce plenty of CO2 as well.

At night when the lights are off and the tank is dark, the plants will also use oxygen and produce CO2.

If you reduce aeration/ surface turbulence during the day (when the tank lights are on), there will be more CO2 in the water and less will be driven out by the aeration. At night when the lights go out you can increase surface turbulence to increase oxygen levels and reduce carbon dioxide in the water.

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Most algae problems are caused by too much light or nutrients, and not enough plants to use the light and nutrients. When this happens algae grows instead of bigger plants.

You can try reducing light or nutrients, and doing more or bigger (75%) water changes and that should help.

If it is filamentous algae then you will have to physically remove as much as possible and reduce nutrients and light, mainly nutrients tho (including sediment in the substrate). You don't have to remove the gunk around the plant roots but if you have open areas of substrate without plants, then gravel clean them to get rid of any gunk.

Make sure you clean the filter at least once a month and preferably more often.