Cyano :(

[martinmcnally]

Alas my new tank (2 years approx now I think) is suffering the same problems my old one did and it seems no matter what I do I am always fighting with cyano.

My lights are LED (AI Vega).
Flow is via 2 MP40s running at max plus 2 return pumps.
Nitrate: 0ppm
Phosphate: 0ppm
I feed only once per day currently New Era flakes. I only feed what is consumed and have a lot of critters that take care of any drop that hits the bottom.

Skimmer is Super Reef Octopus Cone with capacity rated almost double the tank size.

Photo period is noon to 10pm then moonlights on moon-cycle.
Tested the RODI, TDS its coming out 0ppm although for 2 weeks or so there it could have been maybe 2ppm before I replaced the DI resin.

I even syphon the stuff out when I do water changes.

What else can I do? I am tempted to do a 3 days lights out and water change at the end but also worried about loosing a bunch of SPS in the process.

I added some Purigen about 2 weeks ago and I think its helping but hard to tell.




Its done a lot of damage to my German Blue Digi


On another note I started running Carbon 24/7 (BRS Rox) about a year ago and I have had more coral disease this year than ever before. :/

[Aquattro]

why not just hit it with chemiclean?

[martinmcnally]

Originally Posted by Aquattro

why not just hit it with chemiclean?

Its getting to the point where I might have to. I have been considering that a last resort after watching some videos on youtube and doing some reading.

[Aquattro]

Originally Posted by martinmcnally

Its getting to the point where I might have to. I have been considering that a last resort after watching some videos on youtube and doing some reading.

It's always my first resort. It's rare that I get cyano, maybe 3 times, but always hit it with CC and I'm done with it in a couple days. Like you, all the usual suspects are always in order, so really nothing I can change. And if you leave it long enough, it starts smothering corals. So, first sign, I dose.

[martinmcnally]

Hmm I may have to pick some up then.

2 More pics.



My RBTA is gonna take over and climb out of the tank soon haha:

[Aquattro]

Just be aware it will put your skimmer in over drive I turn my cup sideways during treatment to avoid the mess!

[asylumdown]

It's probably not a well accepted theory, but cyano bacteria has a disproportionately high demand for iron, and they've evolved family specific pathways to harvest it from the environment called siderophores that might be able to pick up the form of iron found in GFO. Research around shipwrecks and black reefs have recently shown a strong correlation between the grounding/sinking of iron based ships, and the rapid decline of surrounding reefs as simple algaes like cyano over-take corals. A recent paper linked it directly to the iron rusting out the hull.

There are also half cocked plans to dump enormous amounts of iron in the open ocean to encourage phytoplankton as a form of carbon sequestration. A great deal of the phytoplankton in the ocean is free living Cyanobacteria. Different genera than the kind on your sand bed, but the kinds we deal with have many of the same needs and capabilities.

Anyway it's clearly more complex, and there's more to cyano outbreaks than just iron, but I have anecdotally experienced drastic changes in its behavior just by starting or stopping the use of GFO. I use PO4x4 now, which isn't granulated, it's polymer encapsulated. Produces zero dust and theoretically releases less iron in to the water column. It's expensive as all get out, but I haven't had any issues with cyano since.

[martinmcnally]

So I have been running the red slim remover for 48 hours now but there is still quite a bit left. Wondering if I should remove it now and try again next week or keep it going for a 3rd day?

It is working but slowly.

[Aquattro]

I'd leave it. I usually run it 3 or 4 days, then do my weekend water change

[Myka]

Just follow the instructions on the box. You may need to re-dose again next week or so.

Fwiw, your tank looks quite mature, how old is it? Your rocks also don't allow real good flow around them. I think it's time for a revamp. Cyanobacteria is VERY good at utilizing nutrients and can even bind nitrogen, so even a very small amount of nutrients in the system is enough for cyano to flourish. I have a feeling there is a fair bit of nutrients in your tank, but the cyano is utilizing it so it's not in the water for you to test.