lighting vs cyano

[3D-Reef]

<a href=showthread.php?s=&postid=8119410#post8119410 target=_blank>Originally posted</a> by Fredfish
I think the redfield ratio is of limited value in determining how to completely (or even mostly) stop cyano from growing in our tanks. What would be really interesting is absolute numbers below which cyano can grow.

Getting back to cyano, if you had .2mg/l of nitrate in your tank, using rhe 16:1 ratio you would only need .0125mg/l of phosphate. I am not aware of any hobby kit that could measure such a low level. If you can't measure it, you can never know if you are getting phosphate levels low enough to limit cyano growth.

In my tank, at unmeasurable nitrate and phosphate levels, I can still get vigorous cyano growth. If my test kits are truely accurate, and thats a big if, nitrates will be less than .1 mg/l and phosphates will be less than .00625mg/l.

Practical experience suggests its just not that strait forward.

Fred

I don't know the "absolute numbers" but according to J.C. Delbleek & J.Sprung, 0.015 mg/l Po4 is the limiting point.And Dr.Robert J. Goldstein suggest that keeping P04 below 0.02mg/l.He also says that the blue tin method will read down to 0.007 mg/l. (Lord knows where to get it)
I use salifert test kits and the lowest it will read is 0.015mg/l.

IMO I think the point on the Redfield ratio is to get the bacteria or plants that would normally consume N/P to proliferate,thereby denying the CB for P04.
Allowing the N to fall to low denies the benificial bac' what they need,so a slow down in growth accurs,allowing the CB to grow.
I had cyano in My fuge so I started Co2 misting to get the alge/plants to grow better.Since then the tank has gone down to nondetectable with no3,because of the improved alge growth.The cyano growth was limited untill it hit 0 mg/l,so now I'm dosing it back up to 2.5mg/l with Kno3.And now it's dying off again.
I'm not trying to get a zero reading,just one thats low enough.
Clay

 

[azgard]

my fug is full to the max with cheto. I am thinking of cuting about 1/4 of that out and placing into my display tank for awile to see what the effect may have. I know it will grow but im also intrested to see if infact there is some type of alleopathy reaction.

What do you guys think of this expermental idea.?

 

[Fredfish]

Clay. I'm glad to see someone else is having success with nitrate dosing to stimulate macro growth and limit cyano. Its a hard concept for a lot of folks to get their mind around because we are so conditioned to 'nutrient limit' our tanks.

azgard. Unless you have almost no flow between your main tank and the refugium, any chemicals released by the algae will already be in your main tank.

Fred

 

[Chris2500DK]

One big problem with "unmeasurable" phosphate levels is that the cyano could easily be sucking up every last bit of phosphate released thereby giving you a reading of 0 and lots of cyano.
This would be even more likely in a phosphate starved environment with a steady inflow of nitrogen (from a skimmer) and given the fact that cyano is some of the fastest growing organisms known.

 

[Fredfish]

This is very true Chris. It is the reason that I look for published, peer reviewed studies. A lot of work goes into the design of experiments to ensure that the results aretraceable to a known cause.

Thats why I put in that "for all we know" bit about alleopathy. Although dosing nitrates works well for me to control cyano, and I really like the logic behind plantbrains explanations, his body of knowledge comes from work in fresh water, not salt water.

Fred

 

[3D-Reef]

Fred,I got the magnifying glass out to read the bibliographies so I might find a study for you.But there wasn't anything close to what we are discussing.It may be that this is still too new?

Anyhow,IMO I don't think that "unmeasurable" phosphate is that critical.If you have cyano,you have a build up of phosphate.Wether it's P03 orthophosphate in the water or phosphate P04 on the sand/LR. The question is how to discourage the cyano and keep it from returning.

In the plant section,PlantBrain's plan would only work for those who have a planted tanks.But for someone who doesn't have a fuge I think they could use bacteria instead.ie vodka method. With the vodka (sugar,vinegar) your dosing DOC to remove N/P.
You start at low doses and gradually increasing the amount untill there is a white film.Then cut the dosage by half.
If you have cb you have phosphate and if your dosing DOC.Then the white film (IMO) is bacteria dying off because they are N limited.
So (IMO) you would maintain that DOC level and start dosing No3 to say <2 mg/l.That way your revving up the bac' even more to be taken out by the protien skimmer.
Am I totally nuts here,or what?
Clay

 

[Fredfish]

I keep forgetting that not everyone has a fuge.

You've got me on that one Clay. I don't know anything about vodka dosing other than that it is a controvertial subject.

Fred

 

[Oscaroak]

Hi guys. This is my first post here.I been reading this site for a while but due to my poor English i am afraid to write(reading is not a problem but writing take more experience)
Anyway i want to ad something to help us get a better picture about this cyano stuff.
I did the sugar dosing(about 1 tsp x100 gal-my tank is 120g)and about a week my nitrates went from 40 to between 5-8,but i dont know if was because that or due to the fact that my tank was relative new(like 4 months)i had this big bloom of cyano all over.Now over a month later after a lot of small water changes (5 %) ,a new light (t5 -4 54 w).1'' more sustrate(now about 3'' fiji pink aragonite),my cyano is gone.I dont know is this will bring more light or confussion,but i just want to bring what happen to me and maybe somebady can have an explanation to this.

 

[Oscaroak]

Oops...I forgot ,i also have 2 new maxima clams in my tank which you know are good nutrientes exports.

 

[3D-Reef]

Fred,
I haven't tried vodka,so I can't say that it works,but I have been experimenting a little with C02 and/or vinegar.The alge seems to like the Co2.

I did find something interesting in Marine Fish & reef 2000."Trace Elements" in the Reef Aquaria - Craig Bingman.
He plots the idealized "Redfieldian" ratios for marine nutrients as;

C 106,N 16,P 1,Fe 0.01,Zn 0.002,Mn 0.0004,Cu 0.0006.
L.E.Brand (1991) Limnology and Oceanogrphy 36(8)1756-1771
:wavehand:
Welcome to RC Oscaroak,
Since the tank is only 4 months old,it's hard to say,the tank could have just been in the last stages of cycling.Cyano can show up in a new tank because bacteria haven't yet become fully established.The sugar (IMO) just helped speed up the process.But I'm glad you got control of the cyano,it can be a real pain in the (pick your spot).

Clams are great for a tank.I have a couple of maxima's in My tank that are about 5yrs old now. I think you have to have quite a few of them to make much of a difference in water quality. Although it all adds up I guess.A little here a little there.
Clay

 

[ohan]

Well i had an insane alga bloom i had a carpet of the stuff and used 3 sachets of Green X, i placed the sachets in the wet\dry canister filter i have and within a few days all the alga was gone. Another thing to consider is the position of the tank if it is in direct sunlight during the day this may affect things. Its funny sometimes the simplest things are the answers. But green X from my experience is the go becasue it doesnt affect anything in the tank only the alga.

 

[Fredfish]

What exactly is green x?

Fred

 

[RichardS]

Cyanobacteria is always a phosphate issue IME.

I have numerous fish only tank in which I run copper so no fuges, dsbs, liverock etc. and the only algae that can grow in them is cyanobacteria. As long as I control phosphates then I don't have a problem with cyanobacteria regardless of how high the nitrate levels are.

On reef tanks I always use the same approach. Use of GFO and detritus removal. Has worked every time for me.

 

[mahoneyc3]

i found in my tank that simply pointing a power head at the outbreak area was enough to stop it in its tracks, becuase it didnt allow the cyano to settla and grow, i didnt have what you would call an infestation, but its really the easyest solution and what could it hurt in the long run, just give it a try

 

[ohan]

Quote: What exactly is green x?

Fred

Green X is the name of the product it eliminates high levels of phosphates and nitrates, from memory, this is why it is so good at eliminating the stuff it does.

 

[nickterp]

I know there are many factors behind the growth of cyano, but here is what happened with my tank recently: (so I'm not dismissing other causes)

I've been using exclusively RO/DI water for about half a year now. Frequent water changes, good filtration, etc. About a month ago or so, I started to get bright green algae (cyano) in the front and left of my tank on the substrate. Over the weeks, I would clean it, or remove some of the substrate, and it would grow back almost fully by the end of the day.

Then I started to notice that it was only growing in the front and left half of my tank, directly under only one of my compact flourescent bulbs. Before that I thought maybe it was the window letting sunlight in, but leaving the blinds closed for a few days, and the speedy regrowth dismissed that idea. It wouldn't even spread outside of the front and left half of the tank, but it would regrow every day to cover almost that entire section every time I cleaned it.

Long story short (sorry for so many details), I went ahead and just repleaced the one bulb. Which was a 65 watt PC 50/50 actinic Current USA bulb. Got a brand new one of the same type/brand. Then I cleaned the substrate again that night. Been about 4 days now and there has been little or no regrowth of the cyano.

Thought this was interesting, I know this won't apply to everyone that is having cyano problems, but if you find yourself in a similar scenario as me you should check it out. My bulbs were still less than a year old, but had obviously been losing some intensity.

 

[ohan]

Hey everyone i had a talk to the head of my biology department about cyano and he suggested phospho lock, altough he is unsure about where to purchase this product, he did highlight that the growth is contributed by phosphates and nitrates.
best of luck.

 

[Snarkys]

<a href=showthread.php?s=&postid=7912731#post7912731 target=_blank>Originally posted</a> by Aquaduck
IME lighting has nothing to do with cyano.

I no longer have a issue with cyano but i thought id share my experiences with it and the lighting aspect.

I have two six foot by four foot frag tanks that share the same sump and water with about 15X turn over an hour so they pretty much share the exact same water parameters. At the time the tanks were never getting fed at all because there was no fish in the system.

at one one point i had a 400wMH with a luminarc reflector and a 20k XM bulb over half of one tank and a 8x54w T5 with blue plus bulbs over the other half of the same tank . The 400W MH side had cyano in absolutely plague proportions . To the point that there was so much air in the cyano that it would float the eggcrate to the surface of the water . The t5 side had small patches of it here and there but not much. I should not that the as far as flow is concerned the MH side came first and then flowed over the t'5 side. I ended up adding a 40W emperor aquatics UV sterilizer and that instantly solved the all the cyano on the t5 side but only put a small dent in the cyano on the MH side.

Later when I plumbed the second tank in, I decided to stick with only the t5's. one 8x54W over each. One is all GE 65k daylight bulbs and the other was mostly blue plus bulbs with i think two GE's. Again these tanks share the same water. The new tank light by the GE's again had cyano is ridiculous proportions . if i let it be it would coat almost every surface yet the other tank light with the blue plus bulbs had no signs of cyano at all . eventually i used some chemi clean and it solved the issue almost entirely with one dose. Occasionally it comes back in small patches on the GE 65k tank but normally goes as fast as it came.

because of my experiences, IMHO lighting certainly has a large effect on cyano.

I should note that when i had both tanks on t5's i did have about 5 small fish in there and fed them a few pellets every other day or so but all my tests came up with undetectable nitrates.

To be honest I really doubt much of what "we think we know" about cyano , doubly so after listing to EB's speech on the salt brands at the macna .

 

[Fredfish]

To be honest I really doubt much of what "we think we know" about cyano , doubly so after listing to EB's speech on the salt brands at the macna

Absolutely!

Trouble is that nobody has taken the time to test out various theories under controlled conditions. To be able to confirm any of the many theories put forward you need to be able to reliably repeat tests with the same results a number of times before we can say how and why things are happeining.

As an example, in your case, if you had swapped out lights several times and been able to make the cyano come and go with each switch then you could say with more confidence it was the lights.

In my case, I have a repeatable pattern of cyano growth and die back that corelates with nutrient rises and falls. Its still not under controlled conditions though so I cannot rule out other things for sure.

"if I had a million dollars, I'd buy me a tank... or ten..."

Fred

 

[MCsaxmaster]

I've seen cyanobacterial blooms on reefs in less than a foot of water and at over 100 ft. I'm very skeptical that light spectrum has much if anything to do with the occurance or persistence of cyanobacteria either on reefs or in tanks.

Chris