Unmanageable Cyano

Tellie-Vision

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I have a very bad cyano problem in my tank and I’m looking for any ways to deal with it. I’ve dosed chemiclean four times, my mother and I have spent hours manually removing it for weeks, I’ve lowered my nutrients since I assumed my phosphate being high was the cause (and now my nitrates are too low instead 🫩), and I recently started dosing PNS Probio bc I’ve heard it can help.

There also places where it cannot be manually removed (I have some macroalgae that it has completely coated and some gonis where it is growing between polyps, for example), is there any chance that if I do enough it will just die off in those spots? Or am I doomed? It’s literally everywhere, strangling nearly everything in the tank and it’s incredibly depressing to deal with. I have lost some expensive pieces due to trying to fight this stuff and am scared of losing more… any suggestions are appreciated.
 

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Figuring out why it's blooming is the key.

Can you post your system's water tests results?

Also some history like how old is the tank? How is it being filtered and maintained?

One thing to check is your source water....make sure TDS is 0 for your makeup water.

A system picture might help too.
 
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Figuring out why it's blooming is the key.

Can you post your system's water tests results?

Also some history like how old is the tank? How is it being filtered and maintained?

One thing to check is your source water....make sure TDS is 0 for your makeup water.

A system picture might help too.
I haven’t done an actual ICP test recently; but the tank (40g) has been running since April (I transferred stuff from my smaller tank + dosed microbacter7 to help with cycling so I never had issues with that). Never had issues like this before, up until after bad carbon nearly nuked my tank in early September. Filtered via a 20g sump with refugium. I change 5g of water every week, also dosing AFR every day. This last week I dosed Tropic Marin Bacto-Balance to try and balance out the nitrate and phosphate but it just decimated my nitrates and I was only able to lower the phosphate via lanathum chloride; going to try adding ammonia to fix the nitrate issue.

Last time I checked TDS on my RODI it was 0, but I can check again if I have time later. I checked nitrates/phosphates today and as I mentioned before the nitrates are now bottomed out which is bad, but phosphate is 0.25, down from 1 which was the result I got around a week and a half(?) ago.
 
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tripdad

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There are different strains that respond to different treatments. Try the brand in the pic, I have had success with it when chemiclean failed.
 

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Sneep

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I have a very bad cyano problem in my tank and I’m looking for any ways to deal with it. I’ve dosed chemiclean four times, my mother and I have spent hours manually removing it for weeks, I’ve lowered my nutrients since I assumed my phosphate being high was the cause (and now my nitrates are too low instead 🫩), and I recently started dosing PNS Probio bc I’ve heard it can help.

There also places where it cannot be manually removed (I have some macroalgae that it has completely coated and some gonis where it is growing between polyps, for example), is there any chance that if I do enough it will just die off in those spots? Or am I doomed? It’s literally everywhere, strangling nearly everything in the tank and it’s incredibly depressing to deal with. I have lost some expensive pieces due to trying to fight this stuff and am scared of losing more… any suggestions are appreciated.
I've also been dealing with some difficult cyano over the past several months. According to pictures in my phone, it started around May/June and I haven't been able to completely remove it either. I've been avoiding the chemical route as much as possible, so I've taken all the rocks out and scrubbed them with a toothbrush twice now, along with regularly blowing it off the rocks (though not as often as I need to). Of everything I've tried, replacing my pump had the best results. After reading that cyano struggled to get a hold in high-flow areas, I switched to a higher flow (and newer) pump in my tank, and it definitely gave me more time in between take overs. The flow doesn't reach everywhere, so it still builds up again, but it helped a lot.

I attached a picture of my tank a year ago before the cyano, and from today after it's been cleaned. You can see there are some rocks that it REALLY likes to build up on.
 

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Tellie-Vision

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Someone wanted a picture, I was able to finally take one; it’s like this EVERYWHERE including the sump… when the lights are off it looks a little more green I think?
IMG_9315.jpeg
 
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1. how old is the tank? like how long has the system been running?
2. are you using DI water during water changes?
3. What is your water parameters... and please dont just say its "good" like we would like numbers in the Phosphate + Nitrate area, as those usually point to a direction on why you have the red carpet rolled out to you.

4. You said you dosed chemiclean, did it have any effect? did you dose properly or did you under does because you were afraid of die off?

5. What type of water movement are we looking at? Cyano tends to bloom more in areas with low flow or very stagnet areas.

You can try H2O2, although its a bandaid at best, which is what you been doing.
Id honestly get a test kit which does PO3 + NO3 and get those values.
Then you can see if u need to export or import.

Also i would start dosing your tank with Macrobacter - 7. Its a slow slow slow route, but it works. Only it can take a couple of months for you to see noticable improvement.

Oh how many snails do you have too and how large is the tank?
Trophus are excellent and clearing the red carpet, but they somehow got past evolution and didn't learn to flip right side up and will leave a grave yard of snail shells over time.
 
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It's the change of seasons which always seems to trigger an outbreak of cyano. The big rule in my tank is NO amino acids, ever. And as much flow as possible without killing the tanks inhabitants lol.
 
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mcarroll

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Well daily manual removal is standard treatment for any algae, so find the easiest way to keep up with that.

A UV filter would help at least slow the spread – I would consider adding one.

Check out @Paul B 's DIY micron filter too....with a 1µ cartridge you can filter out things like cyano. (Used with a UV filter they make a powerful combination.)

Lowering nutrients isn't likely to help, at least not much....just messes with stability.

Established cyano blooms create h2o2 (and make peroxidase enzyme), so dosing it won't help.

Chemiclean also isn't likely to help, only in some cases. (Try once, not four times. Have you tested for ammonia during all these treatments to see if that was affected?)

Last, are you sure it's just cyano? Some of it looks "poofy" like maybe it's a form of red algae. (I know cyano isn't cyan, it's red....so that sounds confusing....but red algae is another group of actual algae like green algae. Cyano is more bacteria than algae.)

If you don't use a protein skimmer, that is also something to consider.

But UV/micron will help directly....most other things will be less direct.
 
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Sneep

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Well daily manual removal is standard treatment for any algae, so find the easiest way to keep up with that.

A UV filter would help at least slow the spread – I would consider adding one.

Check out @Paul B 's DIY micron filter too....with a 1µ cartridge you can filter out things like cyano. (Used with a UV filter they make a powerful combination.)

Lowering nutrients isn't likely to help, at least not much....just messes with stability.

Established cyano blooms create h2o2 (and make peroxidase enzyme), so dosing it won't help.

Chemiclean also isn't likely to help, only in some cases. (Try once, not four times. Have you tested for ammonia during all these treatments to see if that was affected?)

Last, are you sure it's just cyano? Some of it looks "poofy" like maybe it's a form of red algae. (I know cyano isn't cyan, it's red....so that sounds confusing....but red algae is another group of actual algae like green algae. Cyano is more bacteria than algae.)

If you don't use a protein skimmer, that is also something to consider.

But UV/micron will help directly....most other things will be less direct.
I've debated adding a skimmer to my tank, and I've been dealing with a cyano problem for a while.
You mention that lowering nutrients would reduce stability, but wouldn't adding a skimmer also lower the nutrients in the tank? I've been physically removing cyano for months now, but I can't get 100% of it, so it grows back. I'm trying to figure out what I can do to get that last little bit.
 
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BryanM

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but phosphate is 0.25, down from 1 which was the result I got around a week and a half(?) ago.
This is a massive drop in a very short amount of time... I get that you're fighting a couple of fights here, but this shocks corals sometimes, and is recommended to lower phosphates much slower than this.
 
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Tellie-Vision

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This is a massive drop in a very short amount of time... I get that you're fighting a couple of fights here, but this shocks corals sometimes, and is recommended to lower phosphates much slower than this.
To be honest, I don’t even know how accurate either result is because I don’t recall people having high opinions of the test I use (API). I only use it as a measure of “it is probably lower/higher than it was last time”
 
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Tellie-Vision

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Is there any way a mod could just delete/lock this thread for me? It’s been more stressful to me than anything and I already have what I need to try a different approach to my issue
 
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mcarroll

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I don't know if a mod will see that, but what you might be able to do is go back and edit the first post with more information such as what you let us know here. (at least that used to be possible...)
 
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mcarroll

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Cyano is in the air and in your water, not just the visible blankets of it around the tank.

stop back in later with an update and let us know how it turns out!
 
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