Green Dust Algae: please help!

Tom Barr

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Matt F.;84588 said:
Hi, Tom--

Thanks for breaking it down.
Sure, one of these days you can take a look at it --when we're both not too busy.
The 3 day brown-out (lights off with glut daily) put a major hurt on it. Prior to the brownout, I cleaned the tank (scraped the glass, wipes down the seams, did several 50% water changes etc.). It took some time for the algae to rear its head again, but sure enough, it did as soon as the photoperiod was increased to beyond 6 hours.
I also noticed the other day that I was lean on my monopotassium phosphate dosing...wonder if this contributed to the algae proliferation. Plants look nice and healthy regardless.

What works so far:
a 3 day brown out works after a cleaning to prevent the GDA from re-attaching to the aquarium walls, but it seems to come back. This GDA doesn't seem to attach plants, just the aquarium walls and rocks. Another thing I notice is that when the substrate becomes clogged with detritus, the GDA doesn't seem that far off. Had this problem in my Mini-M, too, before I tore it down. This time, it's not as bad. The tank looks totally clean now. We'll just have to wait and see if it comes back again.


I have increased the phosphates in my tank.
I have rescaped the right side of my tank and done several large water changes, So far, so good.

Will keep you guys posted.

Detrital build up.............bacterial link?
Lower O2?
Plants still growing but not producing as much O2?
This might be a function of the Excel dosing during the brown out.

Might try more water changes and be proactive there.
Might try H2O2.
Might try 5 hour light for 1-2 weeks.

I'm sure you have tried NOT dosing ferts also(ah would that be so easy?).
The same is true for many species of algae. GDA is not new per se, just about 10 years old in the hobby.
You both might try doing 2-3x a week water changes, see how that does and perhaps the 5-6 hour light period for a week and see.
Algaefix might kill it, but also kills off all your shrimp and microinvertebrates.

Maybe I'll cull some shrimp this way and take out all the nice fires and high grades, then test the tank to see how it does on the plants/eradicates the shrimp.
I'm more interested in it to kill the shrimp/not the plants, than I am the algae. API claims it kills GW and thread algae and Cladophora.
I have a little of those in 1 tank, so perhaps I can kill the lower grade pest shrimp and test it on some wimpy plants/algae.

While I do not have GDA, I think it it can be selective enough to target those other two, it likely should kill GW......then I think there is a good chance at nailing the GDA as well.
I'd be more active addressing and testing, but I've had little chance to work with GDA except 3-4 times and it was short lived.
 

Matt F.

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I know for a fact that GDA is light dependant. When I do a brown out, it doesn't grow at all. That said, a 3 day brown-out will only slow it's growth. The GDA will quickly grow back as soon as you turn the light back on for more than 5 hours (on day 4 or 5).

So a way to inhibit regrowth after a thorough cleaning of the tank is to limit the light as Tom suggest to no more than 5 hours per day.

Frequent water changes do help keep GDA in check. If you do a >50% water change with cleaning the glass every 3 days, this helps. The GDA might come back as soon as you return to the 1 x per week WC.

I think this GDA is seasonal as Tom suggested.

No problems usually during the winter months. Full out blooms during the summer. Thsi was true for my Mini-M, too. I'll have to check when I tore that tank down. I was tired of cleaning every 3 days just to have the GDA come back. If we conclude that this is seasonal, I'll probably stick this out till next winter to see if GDA is dormant during the winter. That would provide us with a "light at the end of the tunnel" and a much needed rest from water changes...lol

I think I've found our GDA friend in other places, too. Although I haven't ID'd this algae as GDA under a scope, this algae is very similar.

Here it is in the planting soil. It's not BGA (doesn't smell bad like BGA). The algae is thick, bright green, and acts just like the GDA that grows beneath the aquasoil in my tank:
GDA001.jpg


GDA002.jpg


Here it is again around the base of a potted plant:
GDA003.jpg


GDA004.jpg


GDA005.jpg


Here it is in a house plant vase (indoor plant submerged):
GDA006.jpg


GDA007.jpg


Assuming this is the same algae (big assumption), the only two things that are in common with my fish tank is the water and the air.
I think we can rule out water, unless San Francisco does something different than SAC. Tom doesn't have GDA and I do (same water source? Hetch Hetchy?
Are the water additives the same year around, or do they change during the summer months?

The other, more reasonable assumption would be the air...spores. We've been doing a lot more watering during the summer. Our windows are always open. Temps are higher (for the most part).

Anyway, this GDA seems very prolific.

Good thing it stays mainly on the glass and hardscape areas with some substrate involvement. It's easy to clean, just labor intensive.

Increased phosphates didn't help my situation. I went from a pinch to a dash last week.

AlsoI clean my CO2 diffusers one a week in bleach. Just broke my ADA and replaced it. I also move its location to directly across from the lily pipe outflow. Maybe better circulation of co2 will have an effect.

Nevertheless, I'll plan to do a water change every 3 days to keep this in check.
 

ajfjavi

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I wasn't aware that indoor aquariums are affected by the change of seasons. Is it the water source changes between seasons?


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Matt F.

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ajfjavi;85100 said:
I wasn't aware that indoor aquariums are affected by the change of seasons. Is it the water source changes between seasons?

I'm beginning to think there is a real connection between the seasons and algae. My guess is that there is more chance of the airborne spores being the cause of GDA than anything in the water, but I have no way of proving that.

FWIW, Here is a picture of my tank (just did a rescape) after a thorough cleaning. I'll take another pic three days from now to show GDA growth. I'm limiting the light to 5 hours per day.
722001.jpg


Let's see if 5 hour photoperiods hits it hard. I know it comes back in 4 days with a very light dusting on the glass with a 6 hour photoperiod.
 
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Matt F.

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So far we've concluded that a 3 day brownout (no artificial light and no CO2 injection) and 5 hour photoperiods inhibit GDA growth. usually by now (three days after a cleaning), my walls would be lightly dusted with GDA.

So, since I am dosing EI, there are two variables CO2 and Photoperiod/light intensity that could affect GDA growth.

The longer the photoperiod, the faster the GDA growth. Does this mean I'm running too lean on CO2 later on in the photoperiod? Or that there is simply too much light?

I wonder.
 

Tom Barr

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See the 2 diagrams I posted on the other thread about O2 and CO2.

Few have the ideal CO2/O2 combo and also........... have algae issues.
The start period of the light/CO2 is the critical time, that first 0-3 hours or so.
Many folks that run 24/7 CO2 likely see better results because they could not ramp up the CO2 fast enough the other ways where the gas comes on at the start of the light cycle.

The ATI dimmer computer helps me, but that's a pricy item.
Still, it allows me to match the uptake and the CO2 system in any which way I chose.

It's easier to adjust the light than the CO2.

A relative pH controller and a good responsive over sized CO2 system make this a good option to get ideal CO2/O2 case listed in the other thread.
I also thought perhaps the seasons played a role, with some green algae, maybe it does, but I got rid of GDA several times.........in different tanks..........and Hair/thread algae and it's still summer.

Knock the light intensity down.
Knock the photoperiod down
Try adding more CO2 sooner.
Try adding more CO2 overall.

You can try each case.
 

dutchy

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I have a low light (30 umol) non CO2 tank that has virtually no GDA.

Toro (1989) found that phytoplankton growth is not a function of photoperiod but of total amount of light per day.

In my constant quest of beating GDA I've also found out that less flow against the front window is better. This seems to be strange, because the flow that was hitting the front window before were the CO2 outflows, so water with high CO2.

Concerning CO2 and O2:

"Two different culture media, namely CHU12 and inorganic fertilizer NPK (20-5-20) associated with
macrophyte (Eichhornia crassipes) extract, were used to evaluate the development of A. gracilis.
Growth rate, development, nutritional value and medium water quality were analyzed. When hydrological
variables in the culture medium of A. gracilis are taken into account, dissolved oxygen and free CO2
alone failed to have any significant difference (p>0.05) between the media employed."

ftp://ftp.sp.gov.br/ftppesca/35_1_111-118.pdf
 
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Matt F.

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Interesting stuff.

dutchy;85214 said:
I have a low light (30 umol) non CO2 tank that has virtually no GDA.

Toro (1989) found that phytoplankton growth is not a function of photoperiod but of total amount of light per day.

In my constant quest of beating GDA I've also found out that less flow against the front window is better. This seems to be strange, because the flow that was hitting the front window before were the CO2 outflows, so water with high CO2.

Concerning CO2 and O2:

"Two different culture media, namely CHU12 and inorganic fertilizer NPK (20-5-20) associated with
macrophyte (Eichhornia crassipes) extract, were used to evaluate the development of A. gracilis.
Growth rate, development, nutritional value and medium water quality were analyzed. When hydrological
variables in the culture medium of A. gracilis are taken into account, dissolved oxygen and free CO2
alone failed to have any significant difference (p>0.05) between the media employed."

ftp://ftp.sp.gov.br/ftppesca/35_1_111-118.pdf
 

Tom Barr

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Neither species is limited by CO2 or 2 as far as algae.

Only plants.

Same thing for fertilizers.

I tried to kill/inhibit a number of species of algae with 200% O2.

That is not..the smoking gun/silver bullet why plants do well and algae do not when the plants are growing well.
Since plants give off lots of O2 when they grow well..it would seem a logical hypothesis, but it's wrong.

The O2 in the root zone from well growing plants, might have some link.

But high O2 will do little to stop algae.

Another paper in English on the topic:

http://www.apms.org/japm/vol24/v24p61.pdf
 

fablau

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Hello guys, I am finally back from my one month long vacation. And I must say, as expected, I am not pleased with my tank situation. I have followed your advice (see previous posts) to reduce my light from 140w to 100w, photoperiod from 9hr/day to 7hr/day and Co2 from 3-4bps to just 1bps and as expected some of my most requiring plants have suffered. Rotalas, Ambulias and Alternanthera Reineckii are the ones that have suffered the most. I am pretty sure to be able to recover Ambulias and Alternanthera Reineckii, but I am not sure about Rotalas (see pictures below).

Instead, other plants such as Swords and Microswords have taken over.

As for my GDA is still there! Much reduced than before, but still there on the front and side glasses.

Now: how do you suggest to proceed? Gradually get back to the previous dosage and light? How much gradually? What do you suggest to do with the suffering plants? I am just concerned to have an algal bloom by getting back to the usual light, Co2 and fertilizer dosage right away.

Looking forward to know your thoughts!

Thanks.

4404da41-1914-e702.jpg



Reduced Rotalas:
4404da41-1924-69ee.jpg



Damaged Alternanthera Reineckii:
4404da41-1930-d4d8.jpg


4404da41-193d-3adb.jpg
 

Tom Barr

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The weaker CO2 competitors are taking a beating............but everything is alive.........
Swords are pretty aggressive and have a lot more storage than the other stem plants.

I'd clean off the GDA good, water change etc.........do not clean the filter, do not trim(topping is okay) by uprooting.
Then up the CO2 and dose, leave the light as is or........... maybe 5-6 hours etc at 140W.
 

fablau

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Thank you Tom, I will do what you suggest.

Just 2 questions:

1. When do you suggest to clean the filters? After a month the pre-filter in my sump is pretty dirt.

2. How do you suggest to gradually come back from 5-6 hr/day to 8hr/day photoperiod?

Thank you again!
 

Tom Barr

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I cleaned the sump block every week in one tank, it kept having GDA, in another and at home, I clean them maybe once they start backing up water in the sump area from being clogged too much.
2-3 months? But the sponge prefilter takes care of most of that.
 

Matt F.

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I would think a reduction of CO2 from 3/4 bps to 1 bps would cause some of the rotala decline (regardless of how many watts you have running). Maybe lean on macros, too?
I leave my co2 injection rate the same when I go on vacation. I just limit the photoperiod from 9 hours to 5 or 6.
As for the GDA growth, I'm still getting a light dusting after 3 days...even with a 6 hour photoperiod.
 

fablau

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Thank you Tom, I will try to wait to clean the prefilter as much as I can.

Matt, the next time I will keep Co2 as usual because I think you are right. I went on vacation other times in the past, and I never touched my Co2 and my plants didn't suffer that much even without fertilizer for up to 3 weeks.

Thanks.
 

sandeepraghuvanshi

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I am watching this thread with great interest.
I have similar problem, and the only way I can remove it is by removing it physically just before weekly water changes.
But it comes back by the weekend:(
 

Matt F.

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Just an update:

My tank is getting better. Been doing 7 hour photoperiods. Made it through the week with only a light dusting of GDA on the glass.
ordered a Vuppa surface skimmer.

i wonder if there is a correlation between decaying leaves (the kind that float on the surfacea few days after you trim) and GDA.
Also wonder if evaporation does, too (maybe just a coincidence)
 

dutchy

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This can be found on the internet:

Control of cell division in a green alga, Ankistrodesmus gracilis
Mikio Kobayashi
+ Author Affiliations
Biological Institute, Faculty of Science, Nagoya University Chikusa-ku, Nagoya 464, Japan
Received May 30, 1974.
Abstract
"The proliferation pattern of Ankistrodesmus gracilis, a species of Chlorococcales, is described. Under standard conditions, various proliferation patterns; di-, tri-, tetra-, or multichotomical cell division were observed. Light-dark diurnal rhythms, LD 12 : 12 and 14 : 10 induced growth patterns which formed two- to several-ten-celled colonies, whereas the rhythms LD 16 : 8 to 20 : 4 induced only the formation of two-celled colonies. These inductions were observed at a cell density of 4.0×106 cells/ml. Dichotomical cell division occured at a cell density of more than 1.5×107 cells/ml. No influence of self-shading on the pattern of colony formation was detected."

Although this might be another genus of Ankistrodesmus. Still it might be a matter of total light, (PAR x time) not photoperiod itself.