Green Spot Algae???

Ranger

Ranger

AC Members
Jun 20, 2001
117
2
18
Everett, WA
Is green spot algae caused by any particular nutrient imbalance and is there any fix for it?

I have a 45 tall that has been planted for about four months now and is doing great except for some green spot algae. I don’t have any other algae problems any more, and all my water parameters seem to be acceptable. The green spot grows very rapidly on the glass (say a very light even coating in a week) but cleans off easily enough. Problem is it’s covering some of the leaves of my plants particularly my Anubias. The covered leaves aren’t dying and the plant turns out a new leaf a week so it’s growing but I would like to have cleaner leaves.
 
Over dosing certain ferts can cause Green Spot. When I use too much Iron I see a marked increase in it.
Also, an imbalance between light and plants can cause it. You don't mention your tank's parameters, but if you have too much light you might try some floaters(Water Sprite, Salvinia etc.) to shade the tank some. They will also help with extra nutrients in the water table.
Len
 
Thanks Djen

I was suspect of both the things you mentioned

These are the stats:

45g Tall(24")

pH6.6, KH 70ppm, (Co2 approx 25ppm) NO3 2.5ppm, PO4 0.5pmm

Now I add iron thru PMDD and Flourish regularly and my plants show no sign of deficiency but when I test for Fe it is undetectable. I've heard some members say that chelated Fe tests don't necessarily show the iron that is really available for plants (and I assume algae) anyway.

My light is 4 watts per gal mixed bulbs from 5500k to 9000k. The result of this being a tall 24" tank is that 4w/g is allot near the surface but at depth it is moderate for the lower foreground plants. Also since it is only 12" front to back, a few tall plants in the rear that reach the surface quickly eclipse allot of the light. I would prefer a tank with different proportions but I have to make do with what I have for now.

The Fe amount intuitively feels like a good start, perhaps I'll try reducing my traces and see what happens.

Thanks for the feedback
 
Your nitrate is low too though. I presume you dose your nitrate and phosphate? I still get green spots on my glass too but not to what I consider an excessive degree. The macro nutrients do need to be kept up in addition to iron and traces.
 
If you have the Anubias in high light area, they are sometimes mor eprone to get Green spot algae.

PO4, K, NO3, etc

PMDD does not add nearly enough iron or traces.

Remember, PMDD was formulated for light values using T-12 bulbs on deep tanks with 1.5-2.1 w/gal, limited PO4, less CO2.

You have over 2x the light intensity(PC's?), 10ppm more CO2, PO4 etc.

You need a lot more traces as a result.
I would not worry about the measurement of traces, it is meaningless to a large degree even when dosing 3-4x the amount you dose now.

I would try this:
More the plants out of the stronger light, add some smaller pleco, up the traces(maybe 2X to start), add more K, NO3.
I trim off infected leaves. Some folks are weird about trimming Anubias, they are quite resilent and sprout new leaves fairly well/fast when given a good tank to grow in.

Regards,
Tom Barr
 
I'd love to see your tank... I also have a 45 tall (36"L x 12"D x24"H). You are using 2 96w PCF lights? DIY CO2 or pressurized?

I have real trouble with red plants (red tiger lotus especially). The light just doesn't penetrate the last ~4" of the tank. I saw a 38g at the LFS yesterday.... same dimensions except only 20" deep and was quite tempted. I'd really like a 36"x18"x20" though. Not sure how many gallons that is... about 50 I think. I like 36" long, but 24" deep is tough for plants.
 
Plantbrain:

Thanks for the suggestions. I do dose heavy on the PMDD because of the factors you mentioned. I double the mixing amounts and dose allot. Still might not be sufficient though.
My plants seem to be growing strong. (The Limnophila will grow about 4 inches in three days once it recovers from pruning and reaches the top third of the tank). I'll try increasing the K and NO3 before reducing the trace.

You mentioned smaller plecostomis (hypostimis) do these eat green spot better then SEA, flying fox, and Ottos?

Supperjohnny:

Yea, the tall style tanks do cause a lighting difficulty. I also think that planted tanks look better with larger front to back distances which the tall tanks generally don’t have.
DIY CO2 for now. I use 2 55w CF a couple of 15x CF for he edges and the rest normal fluorescents. Here is a pic I took this morning after pruning last night

plants1.jpg
 
Looks nice. You seem to have a nice variety of greens & color, but the pic is so small... .send me something larger and I'll host it in the thread if you like.

*Warning, possible bunk info ahead* I've read around here before that it's generally an ok idea to over-fertilize with the trace mixes with frequent, large water-changes. I am by no means experienced so you get what you pay for with this advice.
 
Over fertilization had no effect everytime I watched the other nutrients and over dose(2x what a plant could possibly need or use etc).

It is wasteful and traces cost the most. No real reason to over do it that much.
Over doing it will not make red plants grow.


"Plantbrain:

Thanks for the suggestions. I do dose heavy on the PMDD because of the factors you mentioned. I double the mixing amounts and dose allot. Still might not be sufficient though."

I don't mix it all up into one solution. I use the KNO3, K2SO4, KH2PO4 for the macro and add these directly to the tank dry 2-3x a week along with traces and add the K2SO4 just weekly.
I do not add MgSO4 unless the GH is less than 3 or I know the Mg levels are near zero etc.



"My plants seem to be growing strong. (The Limnophila will grow about 4 inches in three days once it recovers from pruning and reaches the top third of the tank). I'll try increasing the K and NO3 before reducing the trace."

Do you add PO4?
If your CO2 is 20-30ppm during the lighting cycle, you should consider adding this.

"You mentioned smaller plecostomis (hypostimis) do these eat green spot better then SEA, flying fox, and Ottos?"

Yes. Bulldog plecos, Ancistrus, Peakoltia sp are good. They don't really eat it, they prevent the young algae from getting a hold.
You seldom see Amano's picking the glass, or SEA's doing are real work except on leaf edges and on the gravel. Otto's are okay for some algae but are pretty wimpy for this type.

Regards,
Tom Barr
 
Superjohnny: Thanks for the offer I'll e-mail you about it.

Plantbrain:

Much appreciate the advice I'll try dosing some PO4. I've read in some of your previous post about adding a known amount of nutrient to a known amout of water to achieve the correct dosing as apposed to testing. I'll be trying that in the future.

What is KH2PO4 written out in English? Does it have a common source like potassium nitrate (stump remover) and magnesium sulfate (Epsom salts)?


By the way do you have a link to some of your "articles" so you don't have to keep re-typing this stuff?

Thanks for the info
 
You must log in or register to reply here.
AquariaCentral.com
Top Bottom