FAQs on Controlling Cyano/Blue-Green Algae
Related FAQs: Control of Cyano/Blue-Green Algae 1,
Cyano Control 2, Cyano Control 3, Cyano
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Marine Aquarium Algae Control
by Robert (Bob) Fenner
Red slime algae problem 2/17/16
<Matt! Why have you sent 14k plus megs of pix to us. WHY:?>
HI guys and girls (never sure who will be answering so didn't want to be
A quick thanks before I get into it - love the site and have learnt a heck of a
lot from you all - as a relative newbie to the hobby, I really
appreciate the support offered.
My name is Matt - living on the Sunshine Coast in Queensland Australia.
I have listed all my tank info below for reference (hope I haven't left anything
out) but thought it best I ask my question first.
I recently had a small amount of red slime algae in my sump and a bit of rust
coloured algae on some uncovered areas of rock in the display tank. I
treated the tank with red Cyano rx
<A poor idea. SEE WWM re using such... w/o fixing the root cause/s,
allowance/s... BGA will come right back; and in the meanwhile, you may well have
impugned your system>
by blue vet and managed to get rid of almost all of it (trimming the macro-algae
in the sump and syphoning some sandbeds/rock). I know there is still some
photosynthesis going on in the display tank as there are air bubbles on some
parts of the bare rock work but my biggest concern in the red slime algae is
back in the sump and I want to ensure that it doesn't
progress into the display tank and also want to make sure that there aren't any
dinoflagellates!!! There is currently no algae growing on my display substrate
and minimal on the walls of the tank. I have attached a few pics of the
tank and sump (hope they aren't too big in file size) - your
advice/assistance in this matter would be greatly appreciated.
<All recorded, archived....>
I have read a lot about how the Cyano and Dinos occur and treatment including
Bob's books on marine algae id and treatment, and realise there is probably a
lot more for me to read.
Could you please id the algae in the display tank (close up photos of the rock
work) and tell me how to get rid of the red Cyano once and for all (if
<Can't tell w/o sampling, looking through a microscope>
Should I do another treatment of the red Cyano rx?
Is there anything I should be dosing or stop dosing?
Anything else you would suggest/change/do differently?
I am reducing the light cycle in the sump at the moment until I hear back from
Thanks very much for your help and I continue to be a loyal reader - please let
me know if you need any more info or photos.
Matt - Sunshine Coast, Queensland, Australia
<Wish I was there diving w/ you; and a mate of mine in the HHH (Eats Bushes; and
My tank info... (apologies in advance for any spelling mistakes)
I have a 4ft (75g approx.) SunSun curved glass display tank and a 2 ft sump with
refugium. A lot of live rock (possibly 40kg total), a shallow sand bed in
display, 3-4 inch "deep" sand bed in the refugium with macroalgae and some live
rock rubble. Tank has been up for a little over 9 months now - although had a
few issues due to leaks - a total of approx. 350l for the
Fish - 1x Foxface, 1x scopas tang, 1x yellow tang (they actually don't get along
too badly), 1x orange tail blue damsel (male I assume) and 1 blue damsel
(female), 2x blue/green Chromis and currently a dwarf lionfish in quarantine
(feeding on live ghost shrimp I caught in a river mouth and kept in a small tank
Inverts - 1 large cucumber, 5 large trochus snails, 3 starfish (plus a feather
star or 2 if they are still in there), 2 Strombus snails, loads of Stomatella
snails (too many to count), 4 hermit crabs, a few snails from the beach in the
Corals - loads of lps - Goni x 6, hammer x 3, maze brain x 2, jandini x 2, Helio
x 1, short tentacle Fungia x 4, Acan x 6, leather x 2, some xenia, Zoa x 2, some
gsp, 3 quad BTA (one just split to make 3 total), a Duncan, a galaxia and one
sps (Acro)... I think that's it.
Hardware - 2 x 160w full spectrum led (generic brand from china but bright as
hell and good growth rates so far) running from 7-7.30am sunrise with blues,
10-1030am full spectrum, 4-430pm whites off, 6-630pm blues off. Sump light is
just a desk lamp that runs on alternate cycle.
<Great! And macro-algae culture there? A DSB? I WOULD install these
1x aqua one G216 protein skimmer running 24/7 (I am trying to get approval from
my wife to upgrade this to a marine sources skimmer - I know this is probably
part of my problem but I do get pretty good skimmate from it.
Halea 300a chiller running 24/7 - temp runs from 24.9 to 26 degrees and the tank
room is air-conditioned.
2x Jebao rw4 wavemakers @ 4000l/h, 1x circ pump @ 3000l/h.
1x 4500l/h return pump.
I built the plumbing, overflows and sump for my tank - Calfo overflow running
almost the entire length of the back wall, into external overflow using bean
animal syphon (1 full syphon, 1 back up syphon and 1 emergency overflow drain).
I run a filter sock 24/7, cleaned weekly, feed the corals twice a week - target
and broadcast with pieces of fish for the nems and
larger mouth corals, Cyclops frozen and coral diet (made by a guy in qld used by
a number of lfs in my area - mainly Cyclops and microalgae I think). I also add
some garlic and amino to the tank/feed. Fish get fed every 2nd day with new life
spectrum Thera A+ - I ensure it is all eaten
where possible and once a week to once a fortnight with an algae disk.
They also pick at the coral foods.
I have 2 quarantine tanks - 1x4ft and 1x 3ft - both have a little bit of live
rock in but can be replaced with seeded filter media from display tank if
necessary to medicate. Both tanks are cycled. I quarantine all fish for 4-6weeks
at 1.023sg and treat with Cupramine or formalin only if necessary - (I had some
issues with white spot when first starting out in the hobby and learnt my
lesson). I don't, however, quarantine my corals.
I syphon my display tank minimally during water changes due to the amount of
rock in there, change approx. 45l (12%) of the water weekly either using NSW or
red sea coral pro salt mix made up with RO water. My specs are as follows:
nitrite/ammonia - 0 (api test kit)
nitrate - 7ppm (tested using nyos kit) - I can't seem to get them down any lower
phosphate - 0-0.25 (api test kit - looking to get a better one soon)
calc - 360 (lowest) - 440 (highest) - 2 part dosing every 2nd day (api
<Get a better kit mate>
alk - 8-10 (usually stays at 10) dosing every 2nd day - (api test kit)
magnesium - approx. 1500 (nyos test kit) (dosing weekly)
ph - 8.0-8.3 (digital ph meter)
salinity 1.024-1.025 (refractometer)
also dosing weekly - continuum coral elements N (trace elements), strontium,
dosing daily - continuum micro-fuel @ 8ml - I was told by my lfs this is similar
to red sea nopox.
<Mmm; I'd stop this for now>
Gravity fed auto top off using RO water, all the above are dosed manually.
<Let's have you (re?) read here:
and the linked files above. FOCUS on the refugium macro addition/culture, the
DSB addition (at least ten cm. of fine, oolithic sand), AND RedOx measurement.
Cheers, Bob Fenner>
Tuxedo urchin; BGA hang ons issue 11/13/15
Hi, I hope you can help (or confirm) this little oddity about Tuxedo urchins.
I've had mine for almost a year now, and in the last six months everything he
picks up becomes covered in red Cyano?
<Opportunist... conditions in the system are allowing the BGA to establish
itself after a "grinding" from the Urchin. Increased RedOx especially (and what
it takes to get there really) is the measure to use to guide the success of
efforts in improving water quality (more circulation, less dissolved organics);
possibly the incorporation of a live sump/refugium, RDP lighting there, macro
algal culture.... Spiffed up, improved skimming, use of chemical filtrants like
GAC, PolyFilter, adding a bit more live rock, fine substrate to enhance the
I have absolutely no other cyanobacteria in my system. I make sure I relieve him
of his infested trinkets, only for him to pick up a few more which become
covered in a matter of days??
<Again; environmental improvement>
Are they known to do this?
<Mmm; yes; as are all Urchins really... they have "pincers" that penetrate the
test for keeping such off their exteriors, but not the spines themselves>
Thanks for any insight,
<Welcome. Bob Fenner>
cyanobacteria vs. macroalgae lighting
Under typical aquarium conditions does cyanobacteria have a competitive
advantage over red Gracilaria algae/macro algae in areas of low
<Define "typical"... under more/less ideal/ized conditions; no>
I have read on your site that cyanobacteria would have an advantage in low
flow areas (I plan on increasing water flow) but I want to know if I
should plan on adding more light. Tank parameters:
temp=78degF; salinity=1.025; carbonate hardness=10dKH; pH=8.15; ammonia=
0.0; NO3=5ppm; PO4= 0.03ppm.
<More involved of course... >
P.S. Wet Web Media is an extremely valuable site for the home
Anytime someone asks me about starting an aquarium I point them in your
<Ah yes... twenty years on; the site provides all I had hoped for.
Inspiration, information and outlet for my and others efforts. Bob
Re: cyanobacteria vs. macroalgae lighting
Wow! Fast response. The ink on my computer screen wasn't
even dry before I received your reply. I will keep perusing Wet
and the linked files above>
and try to find out what the Gracilaria needs that may be lacking.
My guess is water flow since the shift from macroalgae to cyanobacteria
seems to correlate to removing air stones from the system. I just
wanted to know if lighting could be a contributing factor.
Thanks again, Mark
Cyano Troubles... Rdg. 2/25/14
Good Evening Crew,
I hate to be the millionth email on the subject but I'm having a several
month struggle with this bacteria and can't seem to beat it.
The setup is a 40gallon breeder with about 2-3" of live
<Needs to be deeper>
and about 45lbs on live rock. There is an Eshopps HOB Skimmer rated
for 75gallons and an AquaClear
200 with ChemiPure and Purigen, foam and their ceramic circles, 2
Koralia 800 powerhead in opposite corners pointed near each other. An
its lighted by a 4 bulb T5 fixture with bulbs that are only a couple
months old. The tank tests pH 8.4, 0 Nitrite and Phosphate <
0.25ppm, Ca runs about 420.
There is a small 2" Hawkfish, a 3.5" zebra lionfish and an 8"
snowflake eel as the only inhabitants and they are all spot fed
every other day so as to not pollute the tank with wasted food.
I've tried replacing the bulbs thinking the others were too old, and my
skimmer can be a bit inconsistent with its skimming but it can usually
pull out a nice color of skimmate.
I'm concerned I might not have enough flow or aeration because there is
no sump on the tank
<I'd add... as well as look into competitors, predators... all gone over
and the top layer of water develops that "grease" look
except where the filter agitates it and breaks the surface tension.
<What are you feeding? This film needs to be removed, avoided>
Do you have any ideas or suggestions?
Oh I also change about 5gallons every week with pure RO/DI water. I
appreciate you taking the time to answer this and I thank you in
Happy Reefing. 2/25/14
and the linked files above. Bob Fenner>
Re: Cyano Troubles... not following directions, rdg.
Thank you for quick reply. I am feeding the tank a mix of frozen fish
and shrimp, I was originally thinking that there wouldn't be such a high
waste with the fish being frozen but I will try soaking in rodi water to
see if that cuts back on the nutrients causing the protein slick.
I've also pointed one of the powerheads at the surface to help break up
the slick while increasing the skimmer production.
<... read where you've been referred... there are better means>
The only new question is that you've suggested deepening the sand bed but
I've seen mixed results with that as it in itself doesn't resolve an
<... don't write: READ>
Ich - Red Slime - Mandarin Acclimation (sel., fdg.... gen.)–
Thanks in advance for your time.
<<Hiya John…quite welcome>>
I have three questions, which I'm sure have been answered elsewhere so
feel free to redirect me.
180 gallon with live rock (no coral yet but hope to), T5HO lights right
now but will switch to LED with coral addition, assortment of snails,
crabs, two cleaner shrimp and a pistol shrimp, below tank sump, protein
skimmer, no refugium, stocked early with about 2000 pods which I still
see in the tank and on LR. Tank was set up around October 2013
1. I had an outbreak of Ich (vacation, pet sitter) that wiped out my
tank except for a purple Firefish. Firefish has been in
quarantine (bare bottom tank, sp gravity 1.016)
<<Do consider adding a length of PVC pipe for the fish to hide in.
A ‘bare’ tank is unnerving for any fish, but especially so for shy,
timid species like the Firefish.>>
and the DT has been empty of fish as well. Adequate for
breaking the cycle or at least putting the Ich into a dormant state?
<<Four to six weeks fallow should “break the cycle” as you say…but 3
months will do better towards eliminating any “dormancy” issues.>>
Is a slow drip acclimatization okay to put Firefish back in, and if so how
slow? Slow drip acclimation is fine (though you could do the tried
and true “float the bag, add small amounts of water” acclimation
as well). One to two drips per second works for me in most
cases…but do search the site re ‘drip acclimation’ for a lot more
2. After all the fish were removed, developed an outbreak of red
slime as well as green slime on LR and substrate. Coincidence or
<<Hard to say, but may well indicate a chemical/biological imbalance
that was already stressing the fish.>>
<<Check bio-mineral content and get things back in balance.
Keeping Magnesium, Calcium, and Alkalinity in balance…and at the upper
limits…helps significantly with controlling nuisance slime algae, in my
Thoughts on vodka treatment?
<<I have used this method on-and-off for years (once with disastrous
results, if I’m going to be honest), and do see a benefit when used
judiciously. It’s no panacea, but can be a useful adjunct…though I
would recommend here that you first address the water chemistry and see
if this does the job.>>
3. Getting ready and excited to restock tank. Thinking about
starting with a pair of Blue/Green Mandarins so there won't be a hold
lot of competition and harassment to give these guys a head start.
Thoughts on ORA vs. wild caught?
<<Definitely ORA…these fishes will take prepared foods ( get/use New
Life Spectrum pelleted food) and have a much better chance of surviving
With the pods not really having a predator would the population be
adequate for them?
<<Not likely in the long run…thus the need for animals that will accept
Thoughts on a method or need for quarantine?
<<Mandarins/Dragonets, in my opinion, are less risky…and do much
better…when acclimated right to the display.>>
Would a UV sterilizer ran every other week or so have an effect on pods?
<<Little if any…and likewise re controlling any nuisance organisms. >>
Do these have a better chance of survival as a pair or singly?
<<They can be kept either way…though if kept together do try to get a
true “pair” or at the very least add the male and female to the system
<<Happy to share… EricR>>
Re: Ich - Red Slime - Mandarin Acclimation – 02/20/14
Can't thank you enough for the help and quick response.
<<My pleasure to assist, mate...I hope the info proves useful.
The most difficult question. Coral hlth.
issues; some poss. influences, corrections
Hello again Mr. F.
how are you? I hope all is fine with you .
I have a very important question: what is wrong with my system?
Let me explain: my 250 gallon display was set-up 1 year ago. 220 cm
long, 70 cm wide and 70 cm high. Sump, AquaMedic aCone 3.0 skimmer rated
to 3000 litres, biopellets reactor, antiphos reactor, active carbon
reactor running 24h. Ozone , full line apex Neptune system computer with
the following readings: ORP 350-390, pH 7.9-8.1 , temp 25.5-26.5 and
Calcium reactor, kH 7.2-8.0 , Ca 420-450, Mg 1280-1300.
History: maybe you remember all my inquiries about crypt and fish
disease after my initial ordeal
<A good deal; yes>
With all my fishes dying in the first month because of crypt and
Oodinium, I have spent hundreds of hours reading and learning. I now
have Coral magazine subscription ( maybe one of the very few in Romania
) and dozens of books all read. About fishes , I now have all the fishes
I restarted the system with, P. Hepatus, Chelmon rostratus, A.
Japonicus, pair or mandarins, Z. Xanthurus, Naso lituratus, P.
Imperator ( juv. ) all 10 months now in the system and a beautiful Z.
Cornutus six months now in the tank, all doing very good. So lesson
learned there. ( I have 3. Quarantine tanks , I always perform fw dips
with Methylene blue etc )
4-5 months ago I started introducing SPS corals. I always knew I wanted
a SPS dominated tank with these beautiful fishes I already have ( only
one P. Diacanthus is missing but I will get there also..) then the
problems started. I discovered that I had high nitrates: about 20 on
Salifert test so I started the maintenance program: got rid of the 2-3
cm sand in the DT because of the wrong depth, siphoning of the sump,
changing the media in the reactors etc. I bought some more corals, some
Acropora, some more Montiporas, Stylophora.. Because of a faulty
salimeter ( the paper with the scale moved inside the glass ) the
salinity went to 43 and lots of corals died or dying .
I slowly went back. After that, in September I drilled my pavement and
installed a 300 l refugium with 18 cm sand bed and Chaetomorpha in the
basement with reverse light schedule. After 3 weeks I installed another
200 l tank there with live rock. At the beginning I had some problems
with keeping levels of water ( maybe you remember our discussions )
so the salinity varied 1-1.5 points daily for some weeks.
Before installing the calcium reactor I had some variations in the
levels of kH and Ca. , 1 month ago.
After that I thought everything was stable, so I introduced some more
corals. But I kept losing some of them. Apparently lots of
Montiporas digitata died and also some Acroporas. In November, after the
last addition on sand in the RDSB and some more live rock the
Cyano started. I had to leave for one week and when I come back
more SPS were lost due to Cyano this time ( even thou my friend was at
my house every day feeding and cleaning the Cyano).
<I'd throttle back your carbon additions. In fact, I'd remove the
bio-pellets entirely. This/these are likely driving your Cyano problem
So when I come back I reduced the lighting for the T5 ( I have an
AquaMedic 3x250 w CoralVue ReefLux 14000 K plus 4 T5 x 80 w ATI 2 white
2 blue ) turning them off . ( they were on 12 hours ON ) . I only kept
the MH. The Cyano receded , every day I clean it and blast with a 1200
l/h pump every rock and coral. But it continues to grow on some corals
I fragged some of the Acropora and the frags until now seem to be doing
fine . But every day I discover that another SPS coral is declining.
Other values : nitrates : 2-3 Seachem test
Phosphates : <0.01 Salifert
<Not an issue; in fact, I'd feed more to increase>
Silicates : 0
About the lights: after turning down the 4 T5 I have seen lost in
coloration also in otherwise hardy corals : Montipora plates , so I have
turned them on again and I have measured the PAR readings : bottom 150
-100 between bulbs, middle 230 and top 400. Under the bulbs 1100
micromols/m2/second. . But before turning on again the T 5 (2 days ago )
the readings with only the MH were seriously lower ( 40-60 bottom
between bulbs ).
In the meantime I have lost some Acropora that was with me for 10 months
and survived all that. But there are some Montiporas and some a
Acroporas frags that appear to be doing great so far. I have colonies of
Stylophora and Porites that are ok.
So, why am I loosing SPS corals? Is the stability of the system?
All the changes I have done? Is there something wrong in the water even
if I get all these " normal " readings?
<Toxicity from the Cyano likely is number one; perhaps a lack of
chemical food (too little soluble phosphate) is an issue as well>
It gets pretty frustrating because is not only the money ( by the way
water movement is done by 4 Vortech MP 40 ) but all the energy and study
time ( we have 2 kids 2 and 5 years old so time is important)
<It always is my friend. An important "lesson" in life is to learn how
to portion ones attention. "First things first"... your own health,
happiness; the family and friends about you... petfish are way down the
line of importance>
and the willingness that I feel I am starting to question. I feed
the fish 4 times a day ( defrost and rinsed Mysis and krill and
bloodworms, spectrum pellets, Nori and Spirulina and 2 big fresh clams (
I think this is the term, the black shells) that I keep in my hands
until everything is eaten. All the fish eat a lot and they are fat. But
I arrived in one point when I look away from the DT when I pass by, just
to avoid seeing sick corals . It was not easy at all, all my friends
consider me strange at least do all this for a reef tank, even if they
like it when they come by. Keep in mind that I live in eastern Europe
where LFS are far away and don't stock livestock, and for example a A.
Japonicus costs 250 $. For me, having a SPS tank would mean that all
that I have done is worth it, but something is wrong, and I am not sure
what it is. My wife is supportive, but I would really want to see some
So in conclusion I feel that I have done a lot of efforts and at the
moment I cannot see the results, so it seems it is very difficult, but I
see a lot of successful tanks done with maybe less efforts and I am
wondering what am I missing.
Thank you for your patience,
Andrei in snow covered Romania
<BobF in (today) sunny S. California. Do remove the carbon additions and
increase the feedings>
Re: The most difficult question. More Biology, Less "Technology""
Hello Mr. F
thank you for your answer. I will stop the biopellets reactor, I
was just not sure if my RDSB is mature enough to handle the
denitrification by himself,
<You'll likely see no change in NO3>
my plan was that when the nitrates would arrive to zero I would stop the
About the nitrates, increasing the feeding sounds great, but aren't they
the ones that fuel the Cyano?
<Not necessarily, no... see WWM re the several inputs here>
Shouldn't the desired levels be zero absolutely?
<Never. The chemo-autotrophic life (e.g. corals, many microbes,
algae... ) NEED some/measurable nutrients, including nitrogen compounds
Because I also have a anti phosphates reactor running as well... If the
chemical food might be missing for the corals,
maybe I should feed more amino acids and vitamins ( I do it like once
every 10 days half the dosage ).
<Am not a fan of such reactors in most settings... "More Biology, Less
"Technology"" Is my motto here. B>
Thank you again,
Re: The most difficult question; further input re a/the
mysteries of too much, too little and out of balance nutrient issues
Thank you. The biopellets are off.. will see what happens. I took the
biological route for sure, with the refugium and live rock tank.
What about all the beautiful tanks in several ' tank of the month '
editions that report zero NO3 and PO4 ? Normally you don't see any
outstanding SPS tank presented that has any detectable nutrients.
<Mmm, allow me to "try" explaining: All systems have something/s that
are "rate limiting"... An example, let's think of you and I and our
desire for more "stuff"... We're likely limited by funds/money... Most
aquarium systems have a nutrient limitation... but it is not often
well-understood what this is (a topic of huge possibilities): Your
system is likely being "too driven" by an excess of available carbon...
which is fueling the BGA/Cyano, that in turn is poisoning your stony
corals... I am hoping by limiting the carbon and allowing sufficient
simple nutrient presence, to have your Scleractinians (et al.)
outcompete the Cyano. Now; as to those other systems that are in
"apparent balance"; they have NO3 and HPO4 limitation... BY the desired
organisms taking these up readily; NOT by their reactor/media removal>
I think this is very important. Lots of people out there would benefit
from understanding these basic philosophies.
<Ah yes; I do so agree. Do you understand me above here?>
Please consider that I want nothing less than the most beautiful SPS
tank with colors and corals health. I am willing to invest time, energy,
and money. What would you recommend as optimal values for NO3
<Low, but still measurable.... a few ppm for [NO3], and 0.05-0.01 ppm or
so for [HPO4]>
And after my system description do you think I would need anything else
as hardware or technique?
<Mmm... likely THE best investment in your study, gear is an
understanding of RedOx potential, perhaps an investigation into ozone...
<Thank you Andrei. BobF>
Re: The most difficult question 12/14/15
Oh, and this reading:
Re: The most difficult question 12/14/15
Tank you, I understand.
One more question: I run ozone on my skimmer and have a 350 -380 ORP
reading. What do you think about these values?
<I see... this is very good. B>
Re: The most difficult question; stony coral issues, BGA... ongoing,
Hello Mr. F,
<Andrei; do please change your subject above. The spam filter is
removing your posts>
How are you?
Here things don't look very good aquarium wise.
If someone would ask me I would say that I am now more evolved than any
other time . On the equipment side I run a calcium reactor, 4 VorTech mp
40 synchronised, I use a PAR meter, I do KH and Ca tests every 2 days
and they are OK, I have a refugium etc.
On the knowledge side, I read books, I understand the chemistry ( I am a
chemical engineer ) , I know all the 'tank of the month ' on English and
Italian speaking sites, I know who Julian Sprung, Sanjay Joshi , Daniel
Knop and others are , and I communicate with you....
But my tank has never been worse. ( except for when all my fishes died
). The fishes are ok, but the SPS corals are declining under my eyes and
I don't know what to do. All my tests are ok, I have a apex Neptune
computer with all the readings all right ( including oRP) but my stony
corals continue to die and hardy corals that have survived the 43
salinity and changes in temp in the past are losing colors and get
covered in Cyano. This is drawing me crazy! What could be wrong?
<... as we've been e-chatting re... Mostly they're chemically
starved; and poisoned by the BGA that has been allowed, encouraged to
(over) grow your substrate and more here. Re-read our most recent emails
Maybe the changes brought by the introduction of the refugium - (
100 kg of sand 2 months ago - the last 20 kg of sand only 2 weeks ago )
and some 40 kg of live rock could trigger this?
I am lost and frustrated and I really need someone to help me ( here
there are no reef clubs or LFS that could help me ) .
<Re read.... B>
Cyano and troubles; ongoing; re-laments re Scleractinian
Hello Mr. F
I have understood what you explained but sometimes one can feel lost in
this hobby. But is still only a hobby, so we should get some perspective
and go on learning more all the time. The hard part is that we deal with
living creatures, but " it's all been done before " so...
Here are some photos of some of the corals that were doing great 3 weeks
I am performing 5% ( 60 l ) water changes every day if you agree, I
clean every day and dose amino acids and vitamins ( weekly dose of Fuel
from Seachem divided daily ) .
Could I do something more?
<I wouldn't; no>
Maybe let the lights off for a couple of days? I don't know about this
one, probably not a good idea.
Re: Cyano and troubles 12/18/13
<... change the title Andrei. This was relegated to the spam folder again>
Hello Mr. F
How are you?
Here, I changed all the filters in the RO unit and started doing daily 5 %
I discovered that my RO water had ten times more dissolved organics than
it should ( I don't know the measures units but it had a value of 140 and
after the change of filters had 15 ) .
I also dose amino acids togheder with coral snow from KorallenZucht that is
supposed to facilitate the absorption for the corals. After 2 days the
corals seem to be a little better, but the Cyano started appearing on the
sand, something that before didn't happened . So in my opinion I am dealing
here with chemical starved corals that are attacked by cyani
<A semantic difference: Not "attacked", more like "poisoned">
and need strength and the amino acids that I am dosing for them that
probably is fuelling more Cyano.
Please tell me your feeling about this and what do you think I should do
Re: Cyanobacteria 12/18/13
Thank you for answering,
I know the water changes were discussed, I just wanted your opinion on the
dissolved organics matter.
<... not dissolved organics... Dissolved solids. And no; not likely a large
issue, but an incremental (perhaps a few to several percent)>
Please be more clear if you like, should I continue the amino acids dosing
even if they might fuelling Cyano ?
<I would continue to use>
Thank you and please excuse me if I fail to understand you sometimes...
<Your English is far better than my Romanian. B>
Re: Cyanobacteria 12/19/13
And if we don't communicate again, I wish you Happy and Worm Holydays.
<And you and yours as well. BobF>
Hair algae growing inside a clam
Hello WWM Crew,
I have a problem with a Tridacna clam for which I haven't found an
Some hair algae started to grow on one side of the clam. I didn't take
care of it right away as I was battling these algaes all over my tank. I
have now won the battle but I noticed that some algae managed to attach
on the inside edge of the shell (note : the algaes I fougnt were green
hair algaes, the ones remaining still look like hair algae but
are red-brown and less soft than the green ones).
<Could be... most anything... not necessarily a Chlorophyte. One can't
"tell" the taxonomic group (Division) of algae simply on the basis of
color. Requires microscopic examination and sometimes other testing
(storage foods et al.)>
It is apparently causing discomfort to the clam as the
mantle stays retracted on this area. I've tried to remove the algaes
several time but I cannot get to the root so I am only breaking the tips
away. It has now been several weeks and I am afraid it will eventually
cause the clam to die. I have several hermit crabs and snails but they
don't seem to either care for this type of algae or don't want to go
inside the clam. The only solution which comes to my mind is to block
the shell with a little piece of wood so that the clam cannot close it
and use tweezers to thoroughly remove the algaes.
However, I am afraid this solution will stress the clam and possibly
kill it. Do you have any other suggestion ?
<... this may be Cyanobacteria... or that in origin, accompaniment...
This IS one case where I would avail myself the use of antibiotics...
Erythromycin of a few sorts is sold in the trade/interest... I would
move the clam to a system w/o other life that might be mal-affected for
this treatment. Search WWM with the terms "chemical algaecides"; read
particularly re BGA>
<Welcome. Bob Fenner, USA>
Hello crew, my name is Ben
Ill list my tank/equipment first, 180 gallon DT with a 90 gallon sump
(macro kind of growing-explained below). Skimmer- Aquamaxx cone (rated for
350 gallons), reactor-MR1 with carbon, flow- MP60 and MP 40 (opposite of
each other), lighting- 3 Radian pro's (custom settings at 55%), heating-
two 300w heaters (controlled by apex), Probes- Ph and Temp, return pump-
Mag5, ATO- double float switch, RO/DI 5 stage with double TDS meters. I
not does anything except Alk-explained below.
Parameters are: Temp-79.5 SG 1.025, Ph 8.3, Alk 10.5 NH3 0, NO2 0, PO4
<... trouble w/ NO3 and HPO4... these are needed in measurable
to keep photo-chemo-synthetic life going... Your "corals" are likely
suffering... and the nutrient unavailability is likely favoring the BGA.
How to re-re-re-explain/state this: the folks that sell reactors and
media... make money from perpetuating the idea that zip is better than
some. They're wrong>
Ca 475 Mg 1400, TDS from RO/DI 0
Solomon Island Yellow Tail Fairy Wrasse
Clown Goby- Green
Maxi Mini Anemone - Green
Maxi Mini Anemone - Blue
Sexy Shrimp x5
Peppermint Shrimp x2
Glass Anemone Shrimp
Emerald Crab x2
Porcelain Crab x2
Tuxedo Urchin - Blue/Red
Green Slimer Acro
Plated Montipora - Red
Prism Favia (struggling)
Acan Lord - Red (struggling)
Acan Lord - Blue/Green (struggling)
Most of this came from an established tank however; I moved houses and
upgraded in May of 2013. I went through a mini cycle after the move and
not lose anything. I got the normal diatom bloom but it went away
<No worries; to be expected>
Once the diatoms went away I saw some red patches growing on the sanded
knew it was Cyano or din's since there were some air bubbles.
<Not necessarily indicative. Need to sample, look under a 'scope. Plenty
this is covered/archived on WWM; otherwise I've recently published an
(Amazon) on marine algae, control...>
I did not observe any of this on the rocks at the time. I continued my
WC every other week thinking it would go away on its own but it didn't.
<Ah no; not if conditions favor it over other life>
My macro algae continued to grow well in the sump but the Cyano began to
grow on it so I trimmed that portion of the macro. I eventually trimmed
macro way back because it had tripled in size. Once I did that I believe
the Cyano took off. I started to see it in more places including on my
My macro soon completely died off soon after the second trimming. I
this happened since the Cyano did not really have a competitor any more.
My wife then surprised me with a citron goby. I had him in QT for about
weeks and he was eating pellets. Once he was in the DT he would not go
after the food since the other fish were more aggressive eating the
then began to feed frozen Hikari mysis shrimp however; the citron goby
would only eat one or two I split the cube in half and fed twice a day
make sure he would be eating. Some days I would feed pellets as well.
My conclusion is this, by trimming the macro back, I possibly began to
feed that lasted for several weeks, skimming too dry (not mentioned
but I was-dark coffee color), and loss of several turbo snails (fouling
<Could be contributors>
Which lead to the Cyano and eventually an outbreak.
For a week now I have began to skim more wet so it is more of a tea
reduced feeding to normal (every other day; either one cube feed twice a
day or pellets) added more macro and been raising Ph. My Ph was sitting
8.1 and occasional going to 7.9 but my LFS told me to raise it to 8.4
short time to help rid the Cyano. It appears that it is working since
of the Cyano is starting to break lose from the rocks. I have only kept
Ph at 8.35 for about two weeks so I can't say for sure if it is helping,
more time will have to tell I believe.
Any ideas on what else I can do to help rid of this slime or suggestions
what I should be doing to lesson the odds of it coming back?
<All sorts; ditching NO3, HPO4 filtrant/s, measuring RedOx/adjusting in
many ways, promoting competitors, predators... do you need help using
search tool, indices on WWM? There are articles, likely several hundred
responses to similar queries stored there. Have a look. >
Thank you for you time!
<And you for sharing. Bob (Robert on the eBook biz) Fenner>
Blue-Green Algae/bacteria on live rock
Hi, first time writing although have read a bunch on your site, thank
you so much. I have read much of your algae section but I couldn't
find this described on your pages: if I have overlooked the answer,
please feel free to give me the link I missed.
I am transferring 3 fish (clown fish, yellowtail damsel and yellow
watchman) from my 33 gal tank to a temporary 20 gal, in order to set up
a 45 gal with 30 gal refugium, Caulerpa, protein skimmer etc. I've
otherwise had no issues with parameters, fish are fine. But my
live rock has gotten pretty badly covered with black ("blue green") and
red algae and I don't want it in the new tank.
<You'll either have to bleach/wash the rock (and let air dry) or leave
it out for months outside and brush, freshwater rinse it...>
When I start setting up the new tank, if I scrub the LR under freshwater,
not all the bad algae will come off.
If I put them in the new tank, won't this bad algae re-establish itself?
<Depends on the conditions there; but know that BGA WILL alter the
conditions to suit it... and poison other types of life>
Or is it safer to just start from scratch, boil the LR until they look
decent (I know killing all life), becoming base rock which means I would
<Yet another avenue. Yes. Whatever route you choose, I would use the
existing rock as cleaned/abiotic base, and add a few pieces of new/fresh
Thanks for your help.
<Welcome. Bob Fenner>
Re: Blue-Green Algae/bacteria on live rock
Amazing how quickly you have answered, thank you so much. I will
bleach/air dry the LR. One last question re: this transfer. I have
heard/read that the algae/bacteria is on the solid things (LR, glass,
decor). Would it be risky to use a small amount ( say a cupful) of
original water to seed the new tank? (Although the new LR I guess does
the same thing?)
<Spores will be transferred by anything wet being moved... but; they can
even get here/there (thousands of miles inland!) via the air. Adding
some will not do any harm. It's discounting the mass/majority that you
want to avoid. Cheers, BobF>
Why so many bubbles? BGA...
As you can see in this picture I have hundreds of bubbles popping up in the
algae growing on my live rock.
Wherever there is any kind of algae there are bubbles. While my Purple
Dottyback loves them and enjoys chasing them to the surface, I'm wondering
whats the cause?
<Rapid photosynthesis (notice this occurs only during the day)... of the
pest algae species... They in turn caused by "excess" nutrients, a dearth of
competitors, predators... Am penning my first e-book on marine algae,
control... As this is such a "popular" topic; so common>
I have never seen so many before! And yes, I still have a red Cyano
problem as you can see on my rock and substrate. Should I take out all
affected rock and scrub it again, or just leave it?
<... Did I refer you to reading on WWM? You need to consider, enact other
practices, gear... and solve this BGA issue... much more trouble coming than
Thanks so much!!
<Do search, read on WWM re Cyano Control, Algae in general. Bob Fenner>
Re: Why so many bubbles? BGA... plus
now HPO4, 6/13/13
Sorry to bother you once again....I had a question(ok, probably more
than just one) about phosphates. What's acceptable levels?
<Mmm, depends... less than 1, or 2 ppm, depending on what livestock you
have, what you're trying to do...>
Mine tested between 0.25 and 0.5 ppm. Isn't it optimal to have 0?
<Ah no; not zero... you want/need "some", measurable HPO4 (and NO3) to
sustain basal algal et al. photosynthate life in your system... in turn
supports all else; even if you don't have larger photosynthetic life
like "corals", endosymbiotic-containing life that needs such>
The guy at my LFS recommend a phosphate removing poly filter, which I
<A very good product>
This blasted algae remains stubborn!!! Even with all of my modifications
to prevent Cyano and unwanted algae, it still persists.
<These "things" take time... have I had you read re such... Oh, I see
this below. Let's make a specific rec. Read here:
and "tick off" the list of causes, what can be done to tip the balance
against BGA in your system>
We will be doing another filtration mod next week. Upgrading filter
media to a media basket, adding Chemipure Elite and Purigen. Also will
be adding a ball of Chaeto in the back. I'm sure I will find the right
balance and my tank will finally submit!!!!
What are your thoughts on the media?
<Mmm, I'd add something more permanent that will/does support
anaerobiosis... like Ehfi-Mech, Siporax... there are others, knock-offs>
Should I add something like Seachem PhosGuard?
<Mmm, not with the readings you give here, no>
Keep in mind all of my water tests are still in great range (except
nitrates are still 10-20)
<This is okay for now as well>
and I've read every inch of WWM on all of these topics. Fascinating, to
say the least!
Everyone in the tank is happy and eating well but it's quite the eyesore
having green and red(slime) algae waving back at me from the other
<Will soon be a vague memory>
Thanks SO much once again for your helpful advice!!
<Ahh, thank you for sharing this part, your journey. BobF>
Re: Why so many bubbles?
Oh, good! I have Ehfi-Mech already in place in the back of my cube.
<Ahh! A great product>
Maybe a few modifications using that and the others I mentioned will do
some damage to the Cyano.
Wondering now if I should upgrade the stock return pump since everything
else has been upgraded?!
<Mmm, if it is working... perhaps you can save it as a back up...>
Thanks for the tips!
<Just stating what I would likely do given similar, detailed
Cyano outbreak!!! Sm. SW 5/18/13
I've been reading all of the info about Cyano and hoping this is just a
phase, but I do have a question(s) maybe you could shed some light on.
<I hope so>
I have a 29 gallon Biocube that I have done a few small
upgrades on in the last week. I removed the Bioballs and
replaced with Fluval ceramic rings.
I also bought and installed the stock Oceanic protein skimmer
made for the Biocube, and am still fiddling with it to find the "sweet
spot." And lastly, I added another 7 lbs of live rock to the already 20
lbs I have.
All of this was done to help drop my nitrates. I have also
started doing small, twice weekly water changes as per Bobs
In the last few days I have had an out break of red slime on the front
half of my live sand substrate. I notice in the morning, turning on the
light it has almost disappeared, but by evening it has returned stronger
I feed a very small pinch of New Life Spectrum pellets in the morning
and a bit of Mysis or some other frozen meaty food in the evening. I try
my best to rinse the food, to get any excess juice off before I feed.
Should I cut back on feeding?
<I definitely would... at least until the BGA issue is solved>
I currently house: 1 Purple Dottyback, 1 Fireshrimp, 1 Banggai Cardinal, 2
Percularis clowns and an algae eating Urchin.
I test rigorously, today in fact, and my numbers are good: Specific
gravity: 1.025 Ammonia and Nitrite: 0 Ph: 8.2-8.4 Nitrates: 10-20
(which I'm still struggling to get below 10, but a far cry from the 80
it was a week or two ago.)
Should I upgrade my stock circulation pump and get something to get my
water moving better? Will that help?
<More circulation is better>
Some info says "yes" other info I read says "no."
Will this die off on its own in time and has only cropped up because of
the new upgrades?
<I do hope the BGA will abate; your actions should help>
Do I need more (or less) sand? I have about 2 inches presently.
<More would definitely be better... 3.5-4" about ideal here>
Sorry for so many questions...again. Seems I'm full of them these days.
Thanks so much for all the helpful advice!!! Without this site, I don't
know what I'd do!
<Welcome. Bob Fenner>
Re: Cyano outbreak!!! 5/21/13
Well, I went out and upgraded my circ. pump to a Hydor Koralia 425 gph.
And also added a piece of polyfil to my filter.
My skimmer is skimming and I'm feeding next to nothing (just a small bit
of Mysis that I rinse) and only once a day.
I'm very happy with the circ pump and I've checked for dead spots, and
there are none!! Yay!
However, that dreaded red slime is still popping up on my substrate and
now moving to my rocks. I'm pulling my hair out over this!!!
<Patience Heather... Cyano abatement takes time... sometimes weeks>
My numbers are all still good, as you can see from my last email, and
they haven't changed. (Still struggling to lower nitrates) but at this
point I'm not sure where they're coming from. We test our water that we
change and make sure it's the same as our tank water.
The only thing left is our substrate. We have Ocean Direct Caribbean
Live Sand. We have about 2 in. And we've been advised to add more. How
do I go about adding?
<Simply pour it in... unless it's "too" dusty... in which case you'll
want to freshwater rinse it (swirl around in a clean bucket till it runs
clear... like rice in a rice cooker), then pour it in>
Since the slime is on the substrate, do I remove as much slime as possible
then add sand?
<Fine to just pour on top>
Help please! This Cyano is killing me!!!!
Thanks once again!
<Cheers, Bob Fenner>
Re: Cyano outbreak!!!
Still waiting for the dastardly Cyano to abate. It's now creeping up on
my live rock, and I was wondering, can I take the rock out and scrub
them clean with some reserved tank water/freshwater for the time being?
And the substrate, I don't presently have a vacuum.
<I would get (or make) and use one>
Would using a fish net work to skim it off the top of my sand? If agitated
and stirred up will my fish and inverts suffer deadly consequences?
<Could; I'd vac instead>
(I don't plan on stirring it up though.)
Everything still remains the same in my tank. Just playing the waiting
And lastly, what are your thoughts on the stock Oceanic Biocube skimmer?
<Is a good enough unit for most folks>
Do you recommend an upgrade and if so, to what?
Thanks for all your help and reassurance!! I'll just be sitting here
tapping my foot, twiddling my thumbs till the Cyano decides its through
<This too shall pass. BobF>
Cyano mostly gone 2/21/13
Hi, I've been battling Cyanobacteria for many months now. I am so
close to finally getting rid of this nasty stuff but I just can't seem
to get over this last little hump. This tank setup is a 55 gallon
tank with around 75 pounds of live rock and about 1/2 - 3/4 inches of
live sand depending on where you measure.
<Mmm, I'd add a few more inches of fine sand here; and/or in a tied in
The rock is in the middle of the tank and arranged with lots of tunnels to
reduce the dead spots as much as possible. I have a 260 GPH pump
driving the UV sterilizer. There are two 500 GPH and one 700 GPH
circulation pumps. There is a Penguin Emperor 400 and a Fluval C4
hang on back filter that I use to throw a media bag into when I need to
but mostly they just move water around. They never run floss,
cartridges or bio balls. I have a Reef Octopus BH90 HOB skimmer
which has been fantastic, it may be the only thing I've bought that
actually lived up to the glowing reviews on the internet. The pH
is 8.3 and really does not change. I add Seachem marine buffer
when I mix up salt but that's about it. Ammonia is 0, nitrites are
0 and since I've been waging war, my nitrates have been significantly
reduced and now hover around 2-4 ppm depending on how close it is to the
water change. There are a handful of snails, a few peppermint
shrimp (my Aiptasia war veterans), the last surviving Green Reef
Chromis, a Lyretail Hawkfish and a Coral Beauty so I think I'm stocked
on the lighter side.
For feeding, I take a cube of Mysis shrimp and a cube of something that
has all kinds of random sea critters mixed in and thaw it into a cup.
I feed twice a day slowly to make sure as little as possible makes it to
the bottom. I get three feedings per cup. I have a single 48
inch NO 32 watt T8 fluorescent bulb.
<I'd add more light, to encourage other photosynthetic life>
It's a Reef Sun 50/50 which is 6500K and actinic 420 that is 3 months
I change 11 gallons of water every week (it just happens to be how much
my container holds). I am currently running one cup of PhosGuard
and 1/2 cup of activated charcoal both of which get changed every 3-4
weeks during wartime. At this point, I've not had any Cyano on any
of the rocks for a month or so. The only Cyano I get is little
splotches on the sand bed. It is not a mat, the section of sand
just has a pink hue to it. If I leave them however, they will grow
into a mat after maybe four or five days. I siphon off these
little splotches every other day or so to keep on top of the problem.
So since the start of the battle, I've went from every two weeks to
weekly water changes, bought the skimmer, started using PhosGuard and
activated charcoal and replaced the light. I still have Cyano.
<Yes; you state/have conditions that favor it/BGA, and not other life
So here's what I think the problem is. There is just not enough
stuff to out compete the Cyano.
I have minimal algae growing on the glass, I can go a week without having
to clean the glass and when I do, it's a couple of quick swipes.
There is no algae to speak of growing on the rocks other than coralline
which is spreading. I am toying with the idea of actually
increasing the light to try to get more algae to grow even though the
Cyano will probably grow like crazy at first.
The other thing I thought about was trying to come up with a way to add
bacteria that will also compete with the Cyano.
<The DSB mentioned... do review here:
and the linked files above>
What do you think my next move should be?
I think right now that the Cyano and I have reached a stalemate so
something has to give.
<And we'll be chatting, Bob Fenner>
Re: Cyano mostly gone
Hello! I took the LED hood from my dormant coral tank (a failure for me
but I am determined to try again so I kept it in storage) that has 25 x
3 watt 14K, 4 x 3 watt Actinic and some small number of moon LED's and
was able to cover half the tank. I moved some rocks around to get
more of them under the high beams. I'd forgotten how much I loved
how those lights made the tank look. I was prepared for a massive
Cyano outbreak but it never materialized. There may have been
slightly more red tinged patches compared to the side that still had the
old lighting on it. I've been running the lights for 14 hours a
day to encourage anything photosynthetic to get a move on and start
growing. The nitrates moved down over the period of three days are
very close to zero so something is growing. After the lights have
been on for a while, I'm getting tiny bubbles on the live rock which I
presume to be oxygen though it does not look like anything is growing on
them. They eventually break free and float away. There is
nothing holding them down and they are not the Cyano "red balloons" I've
seen pictures of. The light got something growing and it appears
to have used up all the available nitrates. I hope it's something
green rather than something red. So now is it just a game of
<Unless you do something...>
Do I just keep sucking the little red tinged bits of sand out every few
days? Since I'm trying to encourage things to grow, should I
remove the PhosGuard?
<... have you read on WWM re BGA control, prevention?>
Now for the deep sand bed. I read quite a bit about them the past
few days. I have plenty of room for a sump but I believe I've been
scared away from it because of all the flooding stories of doing one
without a drilled tank. Then again, it's hard to know if the
floods were caused by bad luck or bad judgment. One other option
that I'm not sure would work are some of the hang on back refugiums but
I question if there is enough area to make a difference.
<There often is>
Some are in the range of 20x4x15. Would that even be enough to
make it worth while?
One last idea that may or may not work is since I don't like the look of a
DSB in the main tank, what if I were to slope it towards the back of the
tank so that I don't have 3-4 inches of sand piled up against the front
and side glass? Would I be asking for trouble?
<Would also probably be an improvement. Bob Fenner>
Re: Cyano mostly gone
Brain freeze...yes, I did read BGA control :-)
<Ahh! Well, I do encourage a "multi prong" attack. Limiting nutrient,
increasing light and encouraging useful photosynthetic life as you're
doing; measuring, improving RedOx, employing a DSB, refugium w/ RDP
I exercised your PayPal donate button, seems to still work just fine
though I wish I could do more.
<The thought itself is highly appreciated. BobF>
Re: Cyano mostly gone
Good Morning (from Connecticut),
I've decided to get a CPR refugium later this month.
<Good units in my estimation>
I'll let you know how it works out. I just bought The Conscientious
Marine Aquarist, beautiful photos!
<Ahh! Mostly done by others>
I will let you know in a month or so how it all ends. Goodbye and good
<And you, BobF>
Cyanobacteria - Light color impact on growth? 2/20/13
I've started to limit my light cycles to control my Cyanobacteria
Does Cyano utilize actinic/blue (as used for moon light) or RGB lighting
(as used for my algae scrubber)? If so, I just assume shut these off for
a week or so, to see if this will help with my current scourge.
<BGA span the use of useful wavelengths of photonic energy for
... use your search tool: "blue green algae photosynthetic wavelengths"
Read esp. the Sci. Am. pc.:
Re: red turf war Continues! 2/18/13
OMG,..I totally forgot about testing for nitrate.
In the past, I never had nitrates because of my constant water changes.
So I stopped testing for it.
As far as the phosphate is concerned, I figured, why test for it, when
it's obvious I have it (the algae growth) but something tells me my
reasoning is incorrect.
Going to the store right NOW!
Re Red Turf War Continues! 2/18/13
You're welcome Pam
James (Salty Dog)
New Print and
eBook on Amazon
Marine Aquarium Algae Control
by Robert (Bob) Fenner