Green Dust Algae: please help!

Tom Barr

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fablau;93845 said:
I see.. Hmmm. I am wondering if there is,a way to lower KH...

RO is best, some do vinegar and pre mix in a vat, or HCL,
You could blend about 50/50 RO to tap.

RO is easier over time, no foul chemicals or schtank.
You can drink the RO also, taste better than CO river sludge.

Change the carbon prefilter on the RO, back flush, they will last a fair amount of time.
A trash bin is plenty to do the water changes for this tank size for RO.
 

Tom Barr

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3 degrees is not a bad target.
Less seems best, but then you end up having to use near pure RO.
 

Tom Barr

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32 Gal or those rubber industrial 50 Gal with the wheels on the bottom.

Then you can move it around etc.
I use a small pump to to refill the main tank.

Saltwater folks have to o this since you need to premix the water before adding salt/tap water back into the tank.
So if you need to do a 50% water change on a 350 Gallon tank, you'd need to use several trash bins, or mix, and refill step wise, with just one bin.
 

dutchy

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I stumbled upon something.

I always had good plant growth in my 180G but also problems growing Microsorum species. The leaves were always looking crinkled and they would get worse and die eventually. I also had GDA in this tank.

Besides my 180g tank I also have a 30G non CO2 (Excel) tank. Microsorums are doing great there. These tanks are basically the same. Same tap water, same 6500K light (but less in non CO2) So I was asking myself what makes the difference? No GDA in this tank.

There were three things:
CO2 in the 180G / Excel in the 30G
Light intensity: 70 mmols in the 180G / 30 mmols in the 30G.
Traces: CSM+B in the 180G / Easylife's Profito in the 30G

First I started to add Excel in the 180G. No difference. I didn't believe in a CO2 problem because these plants are very undemanding and I maintain quite high CO2 levels.
Second I lowered the light intensity in the 180G to the same level as the 30G. No difference.
Last I switched from the CSM+B to Profito in the 180G. It was suprising to find out that the ferns started to grow well and pearl after 1 - 2 weeks. I also noticed better growth in a few other species, like P. helferi, which is getting even bigger than before.

But the most surprising was this: THE GDA IS GONE.

So this doesn't make Easylife's Profito to a wonder cure of course. If I take this back to Liebig's law, we can ask ourselves:
What was missing? I added enough CSM+B (Fe levels >1)
What is in Profito that is not in CSM+B and lacks from my tap water? No, it's not Ca. (26 ppm) or Mg. (8 ppm)
Is GDA related to plant growth anyway?

Some questions remain for now....
 
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Tom Barr

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I'd say plant growth is ALWAYS key. In tanks where plant growth is really good, I've not seen any issues with GDA or any algae.
Often times we think plant growth is fine, the same etc, but that is not the case, it can and does go through lulls.

I've never seen GDA IN A NON CO2, LIKEWISE, THERE'S RARELY EVER A BBA ISSUE IN THE NON CO2 TANKS THAT ARE PROPERLY SET UP.

Demanding plants or not, good plant growth and enough biomass with that good growth is key.
Also, switching several things, even if you do so stepwise, does not imply that this did not help.

So say I lowered my light and it cured some algae. In another tank, I did the same thing, but the algae was still there. Was light the only dependent variable? No.
There are others, fixing several things might make it go away on one tank, whereas another might just need one thing.
Ferts and light are fairly easy to rule out, Excel is not the same as adding correct stable CO2.

Plant health can respond very well post algae because there's no algae on the plants.

Provito may use Fe gluconate/Fe DTPA I think also(I also use this added to CMS+B). The green color might be due to the gluconate.
 

dutchy

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So it might be that the Fe gluconate is easier to uptake and this was the limiting factor? In this case my goal was getting Microsorums to grow well, not fight GDA.

Another confirmation that concentrating to grow plants instead of fighting algae works. :)

This GDA has bothered me for YEARS, and I'm happy it's gone now.
 
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Tom Barr

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Well, my own tanks are a good indication of why I do not have algae and when I do, it's always something to do with the plant's health, not ppm's or this or that.

Many of us can easily miss those specific facets relating to growth of the plants, a small lull in growth rate is often times overlooked.
Particularly if the plant looks okay.

I use a few metrics to gauge plant health.
 

dutchy

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I had a problem with certain plants not growing. Trying to solve that I changed from CSM+B to a liquid trace elements products. The problem plants started to grow and as a bonus the GDA vanished.

To verify my previous observation that the development of GDA has something to do with the addition of CSM+B, I repeated it. I added CSM+B again, waited for a week and the GDA exploded. I changed 90% of the water again, added the liquid trace elements and the GDA vanished again.

What I still didn't know, is the cause behind it. The differences between CSM+B and the liquid trace elements product is:

CSM+B has EDTA as a chelator, the liquid has Fe gluconate
CSM+B contains of a limited number of elements, the liquid contains the same as CSM+B but also K, Mg, Ni, Co, F, I, Li, Sn and V.

I add a lot of KNO3 and KH2PO4 so this should take care of the K. My tap water has 8 ppm of Mg, so with 50% waterchanges per week I add 4 ppm of Mg. per week. I found F (Fluor) 0,2 ppm,
There was no listing for Ni, Co, I, Li, Sn and V.

So we can narrow down the cause to two things:
1. GDA grows with Fe chelated with EDTA, but not with Fe gluconate. There is a scientific article which has proven the relation between Fe levels and quantative growth of GDA.

2. GDA grows related to plant growth. certain elements are missing, plant growth stagnates and GDA grows.

To solve this, I added both products at the same time. This should take care of the missing elements / stagnating plant growth cause. The GDA exploded again. This narrows it down to cause number one.

So my conclusion is: GDA grows with Fe chelated with EDTA. If the tank is inoculated of course.
 
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Tom Barr

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Dutchy,

In order to do this, someone else must also be able to to dose plenty of CMS+b and get this result, which is not happening.
I dose very rich levels.

In the past I've tried in vain to grow GDA in my own tanks.
I have a 70 Gallon that had the hair grass and rock like wood and removed 99% of the plants.
I turned the light up to 100%(about 120-140 at the sediment), added CO2 via the NW and post reactor.
Dosed ferts a little light, but plenty for any algae. About 1/3rd EI.

Then waited for algae.
I got some, mostly diatoms but perhaps some GDA.

I added more shrimp, this was for the wood and plants, then tried a bunch of cheap low cost baby bushy nose plecos.
In 1 week, no algae.

It's been starting the 3rd week.

They have done an excellent job. I have been looking for a replacement for pit bull plecos which also have a very good reputation.
I'll see how they perform at a client's who has GDA if we turn the lights up higher.

Still, Fe as gluconate does not last that long in solution, ETDA does not either, but last longer than Fe Gluconate.
 

dutchy

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Hi Tom,

I know this is the weak part in my conclusion. But then again, I can repeat the test and get the same result. Any other factors that could be of influence?
 

Matt F.

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I still battle GDA if I don't stay on top of my twice weekly water changes. Being that I am writing a paper for school my tank was neglected for two weeks, and I spent about an hour yesterday scraping the walls to free them of GDA. For a long time I thought there was a glutaraldehyde/GDA relationship, or a CO2/GDA relationship, or a plant decay/relationship, or a bacterial film/GDA relationship, but this iron gluconate seems like a plausible enough explanation. I, too, use CSM+B. I wonder what form of iron is in Aqua Soil? I wonder if I can replicate your findings in my tank.

dutchy;113416 said:
So it might be that the Fe gluconate is easier to uptake and this was the limiting factor? In this case my goal was getting Microsorums to grow well, not fight GDA.

Another confirmation that concentrating to grow plants instead of fighting algae works. :)

This GDA has bothered me for YEARS, and I'm happy it's gone now.
 

Matt F.

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dutchy;114166 said:
So we can narrow down the cause to two things:
1. GDA grows with Fe chelated with EDTA, but not with Fe gluconate. There is a scientific article which has proven the relation between Fe levels and quantative growth of GDA.

2. GDA grows related to plant growth. certain elements are missing, plant growth stagnates and GDA grows.

To solve this, I added both products at the same time. This should take care of the missing elements / stagnating plant growth cause. The GDA exploded again. This narrows it down to cause number one.

So my conclusion is: GDA grows with Fe chelated with EDTA. If the tank is inoculated of course.

Are you using aqua soil, which is also rich in iron? GDA might be tied to Aqua Soil usage if you assumption/hypothesis is correct. Do you have a link to the article you mentioned?

I haven't been dosing anything in my tank for weeks, if not months. The GDA still comes back, but it comes back at a slower rate than if I dose EI w/ CSM+B. Maybe Aqua Soil is the key...specifically the type of iron they use. Tom did you did an analysis on aqua soil, iirc...

The only relationship I know is that photoperiod can limit or exponentially accelerate GDA growth. How does this play in with the Fe hypothesis?
 
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Tom Barr

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dutchy;114174 said:
Hi Tom,

I know this is the weak part in my conclusion. But then again, I can repeat the test and get the same result. Any other factors that could be of influence?

Well suppose it was say PO4 and not the Fe/trace mixture?
Would you reach the same conclusion?

Suppose I added EM antibiotic to my tank and it got rid of the GDA?
But several others did not?

You see the issue?

It's correlation only.
It is not causative, you cannot say based on the observations and treatments, that X causes Y.

Perhaps it is limiting the plants in one case, but not the other. This was done with PO4 for decades, leading many to believe that low PO4 was key to controlling algae.
But if you limit PO4 more than say a mild CO2 limitation, then........the dependency is CO2, not PO4 really. When they added high levels of PO4, then they got BBA. This was very repeatable.
But...........if you had truly non limiting CO2, then PO4 could be 1-10 ppm without issues. Thus we cannot say that PO4 limitation limits algae, rather, it limits CO2 demand via Liebig's law of the minimum.
PO4 was more limiting than CO2.

When both are cranked up, then no algae is present and plants grew faster and larger.
Such indirect effects are not always easy to find.

But you can bet that if someone is adding plenty of CMS and has no issues with GDA, even though they are exposed often.....that it's likely some other factor.
That said, most would do the switch and stick with it in your case, that does no harm either.

The other option is to overdose the Fe gluconate(SeaChem Flourish??) say 2-3x and see if the GDA comes back.
I bet it will.
 

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Matt F.;114189 said:
Are you using aqua soil, which is also rich in iron? GDA might be tied to Aqua Soil usage if you assumption/hypothesis is correct. Do you have a link to the article you mentioned?

I haven't been dosing anything in my tank for weeks, if not months. The GDA still comes back, but it comes back at a slower rate than if I dose EI w/ CSM+B. Maybe Aqua Soil is the key...specifically the type of iron they use. Tom did you did an analysis on aqua soil, iirc...

The only relationship I know is that photoperiod can limit or exponentially accelerate GDA growth. How does this play in with the Fe hypothesis?

1st tank I saw with GDA was Micheal Rubin's 50 Gallon, 2w/gal of PC lights, wet/dry filter, well care for.
Plain old sand.

Several other tanks, plain inert sands.

I do not think soil has any effect, the 180 Gallon has no algae issues and no matter what I add in there, no algae makes it.
ADA AS.

Loads of CMS+B, DTPA, Fe gluconate etc.

Light is the only factor I've seen that can slow the growth rates of GDA.


I added the pack of bushy nose plecos babies, they mauled the GDA ina client's tank, cleaned the glass and the stone and the wood etc.
I tried this in my 70 Gal at full blast with the ATI light and only a few plants, like a few Buce's and srig of EH, virtually unplanted, I feed the fish/shrimp, but they clean it well.

Even without hardly any plant biomass.

Shrimp alone could/did not do this.

For your tank, 4-6 might do the trick.