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Featured Cyano And Confusion

Discussion in 'Help and Advice' started by damo666, Oct 18, 2017.

  1. doug_amanda

    doug_amanda Admin Staff Member

    Apr 23, 2011
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    "It'll burn out" is probably a poor term of phrase but is commonly used, don't know why,,
    The way I understand it is the cyno is feeding on nitrogenous gas as well as light,
    You can remove the light easily enough but it'll take a good while for the cyno to die off as it still has the nitrogen gas to feed from, you can't remove the nitrogen gas as it's part and parcel of the cycling process and just like diatoms are an indicator that a new tank has cycled (because diatoms can't live in a high ammonia /nitrite environment) cyno bacteria is a good indication that the final stage of the cycle is complete (nitrate>nitrogen gas) and those nitrate eating bugs have gone to work multiplying and munching on nitrates but in turn promoting the cyno.
    as things mature, nutrient and bacteria levels stabilise, nitrates reduce, nitrogen gas reduces, the cyno dies back (burns out) to me its all part and parcel of a balanced and naturally mature system where a little patience goes a long way.

    If the system was an older more mature one then I would have no problem suggesting any red slime removers, I've used chemiclean which worked well on a sudden cyno outbreak on a three year old tank with seemingly no ill affects at all.

    Mr Dave like everybody else I don't want to see your posts deleted, everybody's points are valid, helpful and informative.:thumbsup::thumbsup:
    damo666 likes this.
  2. Gweeds1980

    Gweeds1980 Registered

    Apr 16, 2017
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    H2o2 my friend, h2o2...

    As per my PM...

    For others interested in how you can actually (fact) kill cyano and why other methods don't work... here you go...

    I don't wish to sound arrogant (at least without some evidence lol), but I know this is fact as I spent 3 years studying bacteria on and off, another 2 studying other microscopic biology stuff and finally wrote a thesis on biofilms... there's before, during and after pics available of a 'test' patch of cyano too if anyone is interested...

    Sooner or later all of us reefers will likely suffer with cyano, or to give it its full title... cyanobacteria.

    Cyano isn't an algae, it isn't a true bacteria either, it kinda sits in the middle. It can photosynthesise and it can use organic carbon as fuel. The telltale red colour is when it is photosynthesising... you'll have noticed that it tends to go away at night... it doesnt, it just switches to using carbon instead so the pigment fades away.

    Most of the time we see the red stuff... starts off as a little patch of velvety dark red on the sand... but it can be green or turquoise too.

    That little patch starts to spread and before long it covers everything.

    Cyano is bad... not only does it look horrible, it can smother corals and kill them, it outcompetes useful bacteria for carbon and those great big mats harbour detritus which can lead to a build up of nutrients. This bed of detritus fuels the growth of the cyano as it's full of organic carbon so it becomes almost self fuelling, hence the spread.

    So how do we deal with it?

    You'll have read, I'm sure, a few methods, perhaps even tried some. Below I'll debunk a few methods (sorry) and offer a method which actually kills the cyano.

    But before we start, one thing worth noting... you will never, ever be free of cyano completely. It is everywhere... bacteriums float around our homes, it's in every lump of soil and virtually every wet place on the planet, its under your finger nails right now. You know the 'antibac' soaps and sprays you use at home which kill 99.9% of bacteria? Guess what, cyano is the 0.01%. What we have to do is to make life as difficult as possible for it in our tanks.

    If you trawl the internet for solutions on cyano you will come across a few things which claim to get rid of it... methods and products.

    I'll cover a few of the common ones now:

    1. Blackout period for 72 hours: this seems to work as the cyano stops being able to photosynthesise and loses its colouration. It hasn't died, it is still there, using up carbon instead. If you leave it undisturbed, you'll notice that patch of rock or sand is slightly darker... that's the cyano. Still there. If you're lucky, you'll blackout for long enough for the cyano to shed it's photosynthetic pigments entirely and the colour won't come back. It's still not dead.

    2. Chemiclean... now, this works. It kills cyano... hurrah! What it doesn't do is fix the root cause of the outbreak so you can bet your house on it coming back.

    3. Reduce nutrients to zero. Now, in theory if you could actually reduce nitrate and phosphate to actual zero, instead of a low enough reading to not show up on tests (yes, even Hannah low range phosphorus) then you would see the same effect as a blackout. However, you can't (and if you could all your corals would die) and it won't kill cyano either, unless you reduce organic carbon to absolute zero as well, which you can't do either.

    4. Increase flow. Now, this one is interesting. Cyano will release bacteria into the water column at night which will float about until it settles and then, everything being good, start to grow. So, increasing flow can blast away cyano from the sand and rocks, it'll just float off elsewhere and settle somewhere you can't see it and start to grow again. What flow will do is buy you time... the more flow, the less chance of the cyano settling again. If it can't settle, it can't grow.

    5. Siphon it out. You can't. Or at least not all of it. No way, never. You can't see cyano... all you see is the pigmented mat it uses to photosynthesise. You can't siphon out 100% of stuff you can't see.

    So, with all the myths debunked... how do we actually kill cyano and remove it?

    Well, a multi pronged attack is needed. Cyano has been around almost as long as life itself. It's bloody resilient, you need to be on your game!

    Step 1. Remove as much of the mat as possible by syphoning. This will limit it's ability to photosynthesise and remove all the associated detritus which is helping it grow.

    Step 2. Increase flow. This will stop all the cyano bits from being able to settle. It'll end up in your sump... that's fine, it can live there quite happily minding it's own business.

    Step 3. Stop dosing carbon. You're feeding the cyano. Also check for outside pollutants... pollen, air fresheners and in particular candles can all be sources of carbon.

    Step 4. Introduce as much bacteria as possible... you want to find a strain that will outcompete the cyano. Use microbacter7, Dr Tim's, ATM colony, sand and rocks from a beach or even a river or lake, sand from other people's tanks and your LFS (just be careful with diseases!). There's one product which will really help at this stage - cyanoclean by Korralen Zucht... it is a bacterial strain which outcompetes cyano. Ignore the instructions on the bottle and chuck the lot in (I'm not responsible if it all goes wrong here, although it shouldnt)

    Step 5. H2O2... hydrogen peroxide. If you can, get hold of some food grade 35% stuff... and a few bottles of 6% from a pharmacy. If you can't get 35%, get a LOT more 6% bottles. You may have to visit a few pharmacies as apparently they don't like you buying lots at once... something to do with bombs :). Take out as much rock (without corals attached) that was affected by cyano as you can and mix up 50/50 of 35% strength h2o2 with tank water in a bucket (if you're using 6% then use it pure)


    dip the rock for ten mins or so (30 mins to an hour for weak h2o2) and rinse off in more tank water. It'll fizz like mad in the h2o2... thats good, the bubbles are pure oxygen and shows the h2o2 is killing stuff. Put it into a separate bucket filled with fresh saltwater and leave for another 30 mins. Do the same process with the top layer of sand. You can then put the rock and sand back in the tank. The joy of h2o2 is that once it has shed it's extra oxygen molecule it becomes h2o. So is then totally harmless. This happens within 48 hours, so don't worry if your rock continues to fizz in your tank.

    For affected corals you can dip them in 25/75 6% h2o2 and tank water for a minute. This will be enough to kill off the cyano on the surface but not do too much damage to polyps.


    You will still have a load of cyano in the tank... It'll be floating around in the water and generally being a nuisance. It's ok, you can put h2o2 directly into your tank... yes really!


    Remove any lysmata shrimp to another tank for 48 hours. Only use 6% h2o2 in the tank itself. You can use a syringe to spot treat bad patches of cyano and dose it directly to the tank at a ratio of 10ml per 100 us gallons daily.


    This will ensure you don't end up with higher amounts of h2o2. Be aware that zoas will close up, but they will be fine. SPS and LPS seem to fare better with h2o2 than softies. However, they will all recover.

    Step 5. Leave the tank for at least 48 hours after the last use of h2o2 or until corals have recovered, whichever takes longer. Then use chemiclean as per the instructions.

    Step 6. Fit a UV unit... the bigger, the better, but a minimum of a unit rated at double your tank volume. Just make sure it's good for saltwater use. Ignore the flow recommendations and instead go for 1 x tank turnover per hour or less. UV will kill cyano, but it needs good exposure time to work. This will prevent cyano from getting a hold again in the future, as will all the bacteria you introduced earlier. Obviously this only kills the cyano in the water column.

    Step 7. Sit back and feel smug that you have defeated something that drives a lot of people to start again or even leave the hobby.

    Tank thread :)
    livingjewels, steve861uk and Afonso like this.
  3. Afonso

    Afonso Registered

    Aug 14, 2016
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    We're step 1,2,3? Mate

    Sent from my iPhone using Tapatalk
  4. Gweeds1980

    Gweeds1980 Registered

    Apr 16, 2017
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  5. Staypuft

    Staypuft Registered

    Sep 8, 2012
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    Just to throw more controversy into the mix - salt brand - this can affect the prevalence of cyano bacteria. It was mentioned above but I believe high silicate levels can assist cyano reproduction (PolyFilters can help reduce this) - I have cyano in one of my tanks now and had a discussion with my LFS about salt brand that I use. I’m not naming and shaming as I have used many salts over the last 10yrs with some producing cyano for short periods with none from others. Feeding less and a reduced lighting period have helped me previously but cyano (as said) is a tricky little burger
    Afonso likes this.
  6. damo666

    damo666 Registered

    Dec 20, 2016
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    Hmmmm, interesting. Let's just say I swapped recently on the advice of Burscough aquatics when I went on a day out.......it ties in very nicely with my outbreak. Three large letters to a murder scene in an ocean (cryptic clue to salt brands there lol)
  7. Corey Perkins

    Corey Perkins Registered

    Dec 4, 2017
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    Needed to chime in here since I have just (hopefully) gotten on the downhill side fighting Cyano Hair algae and Hair Algae. First, many, if not everything mentioned here will work. I started by adding Macro to the sump, but no help. I starved it of light for a few days at a time, it would come back. I siphoned and water changed every other day, no help. I ran PhosGuard....no help. I tried Algae Oust and Chemiclean, no help. This crap is hard to pin down. This weekend I pulled my LR out piece by piece (was not recommended by my lfs) and lightly brushed (don't wanna get rid of the good bacteria) it all off and placed it back in. Over the weekend, I would siphon and water change......siphon and water change.....siphon and water change, I did this like 6 times at 5 gallons each (150g tank + sump) . I also had added more Phosguard. This all seems to be working since there is now little to no algae. But, we'll see after a day or two what happens. Also, Phosguard if upstream from your Chaeto, may start killing it off since your taking away the Po4 and No3 it needs. All I'm saying is, there are numerous ways to fight this nemesis, some or all of these weapons may need to be utilized. Just keep plugging away and press forward....Good Luck!
    doug_amanda likes this.
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