So has anyone found the real cause of GDA?

[skiboarder72]

It seems like everywhere I read green dust algae has either no cause or something different. What really causes it and is it true that the only way to get rid of it is to let it go through its life cycle (~3 weeks)? Just trying to get some concrete answers here!

Thanks!

 

[VaughnH]

I can't say what causes it, but I am convinced my problems with it are due to an overly long lights on cycle. I have noticed that it grows only where the glass is in the direct light from either the hood or from the window. I have been using a 10 hour lights-on cycle both times I have had an outbreak of this stuff this year, but just didn't put 2 and 2 together. I have now reduced my lighting time to 8 hours, and I hope I have learned my lesson! So, we will see if that helps once this outbreak finishes its growth cycle.

 

[skiboarder72]

thanks for the info vaughnH, I am starting to think that is the culprit (i am at 12 hours at 2.5wpg now)

another question... to make the stuff go through its life cycle quicker shouldn't be be leaving the lights on longer?

 

[VaughnH]

Tom!! Where are you? It makes common sense to run the lights as long as possible during a GDA life cycle to rush it thru the cycle, and on the Planted Tank forum someone has posted a comment that they tried it and it shortened the cycle considerably. Is that what we should do? I just cut my light period to 8 hours from 10 hours, but if it would rush the GDA to its grave I would increase the time to 16 hours.

 

[Tom Barr]

I'm more concerned about plant growth than algae wars

Running the lights too long is bad for plants.
Less is wiser than more.

Sunlight certainly exacerabtes GDA, even causes it IME/IMO in some tanks.
Clean tanks often get it, powercompact users, never have gotten in a HQI MH's tank before.

Oh it's there and all, it just never grew.

I think if someone wanted to, they could kill it by doing the 4 day blackout + Excel overdosing(1.5X) with daily 80% water changes and glass wipes+ adding EI nutrients back each time.

That should knock back most any algae pretty good and not cause any issues for plants.

From there, make sure good CO2/nutrients, 10 hours of light etc water changes, no direct sunlight etc.

Regards,
Tom Barr

 

[skiboarder72]

I'm more concerned about plant growth than algae wars

Running the lights too long is bad for plants.
Less is wiser than more.

Sunlight certainly exacerabtes GDA, even causes it IME/IMO in some tanks.
Clean tanks often get it, powercompact users, never have gotten in a HQI MH's tank before.

Oh it's there and all, it just never grew.

I think if someone wanted to, they could kill it by doing the 4 day blackout + Excel overdosing(1.5X) with daily 80% water changes and glass wipes+ adding EI nutrients back each time.

That should knock back most any algae pretty good and not cause any issues for plants.

From there, make sure good CO2/nutrients, 10 hours of light etc water changes, no direct sunlight etc.

Regards,
Tom Barr

So it basically comes from light? I knew that because its obviously only growing where light is shining. I have no sunlight shining into my tank and a 65w PC over 26 gallons... How do some people (some have even brighter light!) not get this algae then!
What happened to the let-it-run-through-the-cycle for 3 weeks thing..... I just want this stuff gone, I've got ~25 ppm co2, EI ferts, good circulation... idk what else to do

 

[Tom Barr]

You can still do the 3 week method, but there's the obvious issue: many will not do it because they are not patient enough.

Light alone is not it likely.
It does not appear to have one driver for germination blooms.
Algae with many life stages often don't.

Sunlight, PC lighting seems to encourage it.

You can slide the lights back, bend the reflectors back etc away from the fron of the glass to reduce the strike.

You will also note, the algae tends to grow specifically on glass, it really does not like the plants and other surfaces to the same degree.

Seems a 3 day balckout and Excel would do the trick with harassment methods of scrubing the glass severl times also during that time.

It's not as tough as green water by any means.

I'm not sure as to the cause that induces a bloom, I've had it never appear in some tanks and others only had it for a few weeks then it was gone, no real patterns.

I've seen it with 110 w over a 50 gal tank many years ago.
We cleaned the tank, in 30 min it came back on the glass.
That tank as not high light really, but was PC lighting.

Regards,
Tom Barr

 

[skiboarder72]

Thanks for the info tom! Well actually it looks like some is growing on my plants as well...

 

[Professor Myers]

FWIW: More Plants ! and More Co2 !!!

Looks like you're almost there. What have you got for algae eaters ? I have at least 1 tank Loaded to the I teeth for Bio-Load, and only the Very slightest algae (I see some occasionally). I have to supplement food for the clean up crew on top of 4 feedings a day for the enormous quantity of fish. I don't suggest anyone doing this, but it only goes to prove that algae can be controlled very well by balancing Light, Plants, Co2, and plant nutrition !

Your light cycle is a bit too long. Wattage looks pretty good. Planting looks too light. HTH, Prof M

 

[skiboarder72]

Looks like you're almost there. What have you got for algae eaters ? I have at least 1 tank Loaded to the I teeth for Bio-Load, and only the Very slightest algae (I see some occasionally). I have to supplement food for the clean up crew on top of 4 feedings a day for the enormous quantity of fish. I don't suggest anyone doing this, but it only goes to prove that algae can be controlled very well by balancing Light, Plants, Co2, and plant nutrition !

Your light cycle is a bit too long. Wattage looks pretty good. Planting looks too light. HTH, Prof M

Thanks for the info! These pictures were about 3 days ago, the algea seems to be getting thicker and more dirty looking and seems to be consisting of little tiny hairs attached to the glass that very slightly move with the current. Do the pictures look good? Here are some shots of the whole tank from about 3 days ago. I think I have enough plants... some are growing sideways as it is to get around other plants for light. There is very very little gravel exposed to direct light. I am going to reduce the light down to 8 hours a day (I think having it on ~12 hours a day is partially what caused this). All I have in the tank is a betta and some randomly appearing snails (I saw a big one this morning) that must have come from the plants.

Should I keep waiting for the GDA to go through its cycle, or do a water change and scrub it... its been a little over a week now. Thanks everyone for your continued help I really appreciate it!

 

[Professor Myers]

Nope !

More plants, and Co2...Definitely More Plants and Co2 !

 

[skiboarder72]

More plants, and Co2...Definitely More Plants and Co2 !

My crap test kit says I'm up around 20 ppm for co2 based on the kh, ph (ph dropped .8 from the tap). But I do have another hagen bubble ladder on the way with another diy co2 ready to go when that gets here so I'll have double the co2, and more consistent co2 then. I have another jungle val and dwarf sag I could put in the tank but I don't want to disturb the growing algae and restart the cycle! So again... should I let it go through its cycle or just clean it and do a water change (its been a week and a half) and plant a couple more plants (even though I don't really have space now...)

 

[Tom Barr]

The hagen bubble ladders are neat to watch, but rather ineffective,

If you use DIY, try the DIY reactor I have outlined, it does 10X what the ladder will do.

Regards,
Tom Barr

 

[skiboarder72]

The hagen bubble ladders are neat to watch, but rather ineffective,

If you use DIY, try the DIY reactor I have outlined, it does 10X what the ladder will do.

Regards,
Tom Barr

Not to disagree with you or anything but I think the hagen ladders do quite a bit in terms of disolving the co2 in the water... (i know you are arguing micro bubbles do more...) a bubble comes out with approximately a radius of .2cm then when its all done radius of .05cm that math gives me a little over 98% diffused into the water... with good circulation i think this would be a very affective way to get co2 into the water... most people say that 1 2 liter is enough to do a tank ~25 gallons as far as co2, and with two of those even if my bubble ladders suck, I think its safe to say I'll have enough co2

here is another picture

 

[Professor Myers]

On The Contrary...Not the same at all !

A Co2 ladder is co-current. (There is no positive pressure) Tom's little DIY Reactor is counter current. (This forces a greater "positive"ambient pressure within the vessel) multiplying contact time, and Greater Co2 saturation exponentially. While the design itself is quite efficient, it also supplys what is IMHO a neccessary edge to Yeast Reactor systems. Remember...you have relatively little expansive energy compared to tanked Co2, and this does actually make a difference in saturation in a liquid environment ! Savvy ???

Just a heads up. You can also get an edge on organic sytems by using a nutrient rich substrate like ADA Aqua Soil Amazonia, Seachem Flourite or Onyx. With a yeast reactor, and 2.5W lighting I'd go for the ADA/ASA

Mi Dos Centavos, Prof M

 

[Tom Barr]

Tell you what, I'll outright bet 20$ that the DIY reactor will kick these things butt.
Wanna take me up on it?

I'll pay pal you if you honestly believe after using the DIY reactor for 2 weeks with the same DIY source etc.

You pay me 20$ if I'm right, I'll pay you 20$ if I'm wrong.

Also, I say you can drive any 25 gallon tank at a max level with one 2 liter Brew(changed weekly) if the room is relatively warm(75F etc or higher) and 1/2 teaspoon Yeast + 1 cup sugar.

You use 2 such 2 liter and the 2 ladders now.

It's not so much about dissolving alone, it is about distribution as well.
This is especially true with larger systems.

Now why would I do this bet?
I'm not much of gambler, but I know if you try it, you'll be a lot more successful, with DIY.

I did DIY for over 10 years on tanks from 10 to 90 gallons.
All the CO2 reactors I made where a reflection of trying to get the most out of the DIY method.

Applying that to the CO2 gas tanks made things very easy.
Try the DIY reactor, it's cheap and easy to make.

What do you have to lose there?
I can explain why and all, but the best evidence is actually trying it and seeing it.

Regards,
Tom Barr