Green Dust Algae on the glass. UV?

ShadowMac

Lifetime Members
Lifetime Member
Mar 25, 2010
1,043
13
38
Grand Forks, ND
dutchy, I use RO water and a GH booster (1/2 tsp) to probably about 15 gallons or so of RO water (at 50% water change), would my GH still be fairly low?

There are so many confounds within a tank it seems difficult to test some of these things. For example, if i reduce my GH booster and GDA reduces, i can't necessarily attribute that to the reduction in GH. At this same time, plant mass is increasing, CO2 and fert consumption is increasing, increased plant mass reduces flow. In my tank, since it is a new scape (some new aquasoil, new filter with old media) there is also the possibility of decreased bio filtration that improves over time, as well as an increase in fauna when I add new fish (that one can be controlled for).

How do you plan to test? what will your tank be like? Do you have something stable you can run the tests on? I wouldn't be willing to play around as I'm not as experienced as you and don't want to really goof up this new scape. its a tight rope for me!

I'm curious how these "test" setups work and how you control for the possible confounds. (I could start a new thread if this is too far off topic)

How would one identify more than one genus in such a small organism? I doubt there are morphological identifiers. I'm assuming you would need to sequence the DNA and compare to a registry of known genotypes. Does such a database exist for algae? Are the enzymes available for such a test? It would be interesting to know if there are a multittude of varying genotypes that are adapted to varied environments. Although, that knowledge would be useless to the common aquarist as they would have no way of determining which strain has infested their home aquarium.
 

dutchy

Plant Guru Team
Lifetime Member
Jul 6, 2009
2,280
5
36
63
The Netherlands
I haven't seen any differences in GDA development and plant growth. My plants are like weeds. GDA is the only algae I have, nothing else. If plant growth was an issue, I should also have BBA etc. I ruled this out quite long ago.

Testing is easy, as I keep the new parameters stable over a week time. At the normal maintainance day I compare the GDA development by taking pics. I write down the water parameters for that week. Easy to compare.

Actually, there is indeed an algae database which you can find at www.algaebase.org. You can also see that there are 136 different algae of Ankistrodesmus, the family GDA belongs to.

Difficult without a microscope.
 
Last edited by a moderator:

ShadowMac

Lifetime Members
Lifetime Member
Mar 25, 2010
1,043
13
38
Grand Forks, ND
do you manipulate any of the variables while holding others steady? or do you compare GDA growth to your measurements without any manipulations?

Thank you for sharing the info on the database, it would make sense that algae is an area of heavy research and such things would be available if you knew where to look and what you were looking for.
 

dutchy

Plant Guru Team
Lifetime Member
Jul 6, 2009
2,280
5
36
63
The Netherlands
I modify just one parameter at a time, while keeping others steady. If I notice a change, I repeat the test. I'm testing on my display tank. That's no problem, I'm not afraid of algae since I can beat it quite fast....except GDA.
 

ShadowMac

Lifetime Members
Lifetime Member
Mar 25, 2010
1,043
13
38
Grand Forks, ND
thanks for replying.

For me, algae is best avoided as I usually do as much harm as good when trying to mess with it. Still learning, but getting better.

good luck and keep us posted if you have any significant findings.
 

Tom Barr

Founder
Staff member
Administrator
Jan 23, 2005
18,699
786
113
Well, the key to figuring out algae, is being able to induce it. What causes the spores to germinate and form a bloom i the aquarium?

Correlative factors can help, but do not show cause. Even if you come up with a cause, there may be more than one cause.

It is much better to test the germination on purpose.
I've tried doing this with GDA, and I have not come up with a good consistent method.
I tried repeated exposures..........

Same light intensity, same fert dosing, same tap, same and dissimilar sediment types, O2 same, CO2 was the only one I had much difference on over the day cycle.

Does this show that CO2 is the key?
No.

I tried messing with that on another tank that was "immune", nope.

I did have a lot of stem plants and fewer stems, more open spaces in the other tanks, so more stems and biomass seem to correlate, most other folsk also seem to have this as well.
 

jerrybforl

Lifetime Members
Lifetime Member
Mar 7, 2010
1,034
3
38
43
Miami Beach, FL.
I have the same problem and cant seem to get rid of it! I have BBA on my DW and slow growing plants. Would flow be a problem? I dose EI. The tank is 29 gallons but I dose the 40-60 gallon range. I use RO water with Seachems Acid/Alkaline buffer ratio and equilibrum. I have 55 watts mounted about 4 in above the tank so the light is about 30 or so in off the substrate. Could CO2 but a limiting factor? I use a glass diffuser on it but I'm not sure if I'm getting enough CO2 in the tank. Also, how do you guys measure how man ppm's you have of each compound in your tank? Hope someone can help me.
 

dutchy

Plant Guru Team
Lifetime Member
Jul 6, 2009
2,280
5
36
63
The Netherlands
Flow / CO2 dispersion is certainly of influence considering BBA, although the culprit is suboptimal plant growth. Get your plants to grow optimal and the BBA won't survive, even without using Excel. Trim and prune aggressively, if you have to daily.

Establishing CO2 ppm's is impossible if you can't make in-situ measurements. You can use the pH/KH table as a starting point and from there adjust as needed. Other ppm's can be measured with test kits which, although possibly not very accurate, give you an indication.

Nevertheless, if you dose EI it's not really helpful to know exact ppm's. It will always be enough anyway.

At 29 gallons with 55 Watt just 4 inch above the tank the PAR will probably be higher than 30, and CO2 demand will be high too. I'd raise it another 4 inch and see what happens with plant growth and algae.
 

dutchy

Plant Guru Team
Lifetime Member
Jul 6, 2009
2,280
5
36
63
The Netherlands
Tom Barr;68688 said:
Correlative factors can help, but do not show cause. Even if you come up with a cause, there may be more than one cause.
I agree.

Tom Barr;68688 said:
It is much better to test the germination on purpose.

Every tank I set up gets it, CO2 or non CO2. That means there is a common cause in which CO2 doesn't play a role.

Tom Barr;68688 said:
I did have a lot of stem plants and fewer stems, more open spaces in the other tanks, so more stems and biomass seem to correlate, most other folsk also seem to have this as well.
Well, you've seen the pics of my tank. Full of plants, great growth, but also full of GDA. I haven't seen any correlation here.
 
Last edited by a moderator:

Tom Barr

Founder
Staff member
Administrator
Jan 23, 2005
18,699
786
113
My tanks with fewer stem plants and more open rarely have ever had it. I cannot think of any tanks I've ever had except the full O stem plant tanks, even if I hack them back etc.........but the lawns of HC, Gloss, Starou, C parva, tennellus, Lobelia, hairgrass etc........never got it.
 

yme

Lifetime Charter Member
Lifetime Member
Nov 30, 2005
643
19
18
To add to the conversation:

I think it is also good to realise that not everything that grows fast/reattach itself on the glass is GDA.

e.g. I have for the last years this algae growing on the plants and front glass of the tank. every two days I have to clean the glass. After half a day you can already see a green haze on the glass. (you can imagine that the plants are also quite covered by it)

however: it is not GDA.

3.jpg


and two pictures of the same algae on a plant (easier to make picture :)

1.jpg


2-1.jpg


greets,

yme
 
Last edited by a moderator:

yme

Lifetime Charter Member
Lifetime Member
Nov 30, 2005
643
19
18
yup,

I think it is Oedogonium as well. :)

greets,

yme
 

ShadowMac

Lifetime Members
Lifetime Member
Mar 25, 2010
1,043
13
38
Grand Forks, ND
just to add something as well, a strange observation with my GDA...it does not grow above a certain point in my tank. There is literally a straight line circling the tank. Curious, i have no idea why that would be. I thought maybe light inhibition, but two 24W T5HO's on a tall 37 gallon didn't seem like enough to cause light inhibition. The plants all look great, best growth I have had yet in the tank. CO2 seems nice and stable, as measured by about a 1 degree pH drop over the course of the lighting period, kH is unkown as I haven't measured it with my RO mix yet.

Just thought it was strange about the GDA.
 

pat w

Member
Nov 4, 2009
462
0
16
Daphne, AL (east Mobile Bay)
I have the same sort of thing ... glass evenly covered from the substrate to a very visible straight line around the entire tank. Mine seems to be about the same point that I stop draining the water during water changes.
CO2 maybe?

Pat
 

ShadowMac

Lifetime Members
Lifetime Member
Mar 25, 2010
1,043
13
38
Grand Forks, ND
ya know i didn't think of that...could be the same point for me. This weekend I will drain more and see if the line changes.
 

ShadowMac

Lifetime Members
Lifetime Member
Mar 25, 2010
1,043
13
38
Grand Forks, ND
why does it not reinfect that portion of the glass then? strange that a water change would prevent it from spreading up further, even after a week.
 

dutchy

Plant Guru Team
Lifetime Member
Jul 6, 2009
2,280
5
36
63
The Netherlands
ShadowMac;68780 said:
why does it not reinfect that portion of the glass then? strange that a water change would prevent it from spreading up further, even after a week.

Pronably being out of the water kills it. It also reattaches, it just takes longer.