Nasty Cyano Outbreak

Robb05

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Need help! 20 gallon tank with some live rock and clownfish has been setup for almost 10 months. I moved it to a different spot in the room. In the new location the tank got a little bit of sunlight in the morning. I am not sure if this was the cause but I think it is. I was doing regular water changes (5 gallons every 2 weeks), and I was not overfeeding. I had no issues before I moved the tank. A few weeks after the tank was moved the cyano started accumulating. All of the testing is within the optimal ranges (PH, nitrates, phosphates, calcium, alk etc.). However, the nitrates and phosphates were very low. Maybe too low ? Also, the flow in the tank is good. The outbreak is pretty bad. I have used the chemi clean treatment (no help). Water changes, I have scrubbed all of the rock with a toothbrush to try to clean it and cleaned out all the sand and within a few hours it is coated again with the long red hair/slime. I have put a black out curtain on the window that was affecting the tank and still no luck. Not sure what else to do at this point. Help!!!!
 

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mann1139

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My method for cyano has been:

1. Lights off for a week.
2. Reduce feeding if possible.
3. Vacuum as much as possible.
4. Remove rocks I can and scrub.
5. Phosphate remover in tank.

If that doesn't work, red slime remover, but you have to follow the instructions exactly.
 
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Robb05

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My method for cyano has been:

1. Lights off for a week.
2. Reduce feeding if possible.
3. Vacuum as much as possible.
4. Remove rocks I can and scrub.
5. Phosphate remover in tank.

If that doesn't work, red slime remover, but you have to follow the instructions exactly.
I've had the light off for a few days and it looks like it is getting better already. Does that mean it was on too much or too strong ?
 

mann1139

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Cyano needs light, nutrients, and lack of flow to form.

Lighting is the fastest of the three to cut off, but not the way you want to control the cyano.

Long-term, its the nutrients you want to remove. Macroalgae, phosphate remover, increased water changes are all ways to remove the nutrients.
 

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