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Green spot algae question

Q

Qwedfg

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Joined
21 Feb 2022
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139
Location
Rhode Island
I have been having an issue with green spot algae in my relatively new tank. The tank has been up for 3 or 4 months now and recently green spot algae has been appearing my aggressively on my glass. The tank is full of stem plants, I use apt complete for fertilizer at the recommended dosage, have aquasoil for substrate and my ph drop at lights on is about 1.1-1.2 (I have been slowly increasing from about ~1). For lighting I am using a Chihiros WRGB 2 at 40% power (RGB all set to 40% power) which is significantly lower than the last time I had the tank set up.

Each water change I blow the substrate with a turkey baster and whenever I pull up stems to replant them I do a more significant cleaning of that section of substrate. I have read that phosphate can be linked to green spot algae and have been thinking about going back to mixing EI ferts as my APT complete is almost out. With the widespread success people have with APT I don't think that is the problem but I am curious about how to fix the problem so it seems like an easy thing to try. Can anyone give me advice on a next step to trying to eliminate the green spot algae? Other than that my tank is algae free.
 
I’d generally associated GSA with too much light, occasionally/potentially a long term build up of too much iron. If it were on the plants too, I would suggest it might be a systemic balance issue between lights, ferts and CO2. But if it is just on the glass, the glass is a prime candidate for GSA because it is such a reflective surface. That said, you say you have the lights at 40% already, which seems reasonable.

You could try dropping them more, to say 30%, to see if that helps, or you could try adding a DIY shade the reduces the light hitting the glass.

For me the main indicator would be plant health, so if you’re not getting algae on the plants, then front glass cleaning is sometimes just something you have to live with on some tanks.
 
Thanks for the replies.

I think I will try going back to mixing my own ferts and going EI again to see how it goes. It seems like there are a lot of different targets for NPK that people use....could I get a recommendation on levels? Also I just have CSM+B and DTPA Iron for micros...I noticed people go pretty light on traces these days ...what would be a good iron level to target for CSM+B?

Thank you
 
Nitrate 20–30 ppm
Phosphate 1-3 ppm
Potassium 20-30ppm
CO2 30ppm
Zak Rafik

Thread 'Dosing of CSM+B and Fe-DTPA 11%'

Hi guys,
I'm going to dose CSM+B and Fe DTPA 11% for my 80 gallon tank (310 Ltrs)
My target for Fe is 0.7ppm per week.
Dosing plan :
3 times a week.
Using a stock solution of 500ml water+traces.
Can the members here guide me on how to achieve this target.
What ratio is the CSM+B to Fe, is it 2:1 ratio?

I just bought a small weighing scale and so would prefer the values in grammes.
Thank you in advance.
Cheers.
 
Andy Pierce said:
For me increasing phosphate to 7 ppm seemed to sort out GSA. Others have had less success though it's easy enough to try.
Click to expand...
This worked for me by adding additional KH2PO4 to my existing APT 3 regime. I subsequently moved to DIY EI dosing about 6m ago and incorporated the extra KH2PO4 as part of it. Didn't eradicate GSA but substantially reduced it.
Cheers
 
TrevC said:
This worked for me by adding additional KH2PO4 to my existing APT 3 regime. I subsequently moved to DIY EI dosing about 6m ago and incorporated the extra KH2PO4 as part of it. Didn't eradicate GSA but substantially reduced it.
Cheers
Click to expand...
What targets did you use for NPK if you don't mind me asking.
 
I get GSA only on glass and AR mini. I tried to increase PO4 to 3 ppm and reduce iron dosage, did not help. Ended up just clean the glass often and cut leaves in a while. Also looking for a solution. All other plants are fine.
 
nijat11 said:
I tried to increase PO4 to 3 ppm and reduce iron dosage, did not help. Ended up just clean the glass often and cut leaves in a while. Also looking for a solution. All other plants are fine.
Click to expand...
This is also my experience. I heard rubberlip plecos can be good at eating GSA, I may need to get some. Anyone know any other GSA eaters?
 
Hi all,
RickyV said:
Anyone know any other GSA eaters?
Click to expand...
Nerites (Clithon or Neritina spp.) <"will eat it">, they can crunch through quite hard surfaces to get at the chlorophyll. I associated GSA with hard, alkaline water, where these snails will be happy.
Themuleous said:
....... they even seem to sort out green spot, which is a sod to clean off glass.
Click to expand...
rockalgae-resize-jpg.77333

RickyV said:
I heard rubberlip plecos can be good at eating GSA, I may need to get some
Click to expand...
I didn't know that.

I think the problem with Chaetostoma spp. is that they have fairly specific habitat requirements <"PlanetCatfish.com - Chaetostoma formosae (Loricariidae) Cat-eLog"> which doesn't make them very suitable for most tanks.

cheers Darrel
 
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My water is very soft and still get GSA. I use RO and remineralize to 3.5-4 gh with no kh added.

I am going to mix up a batch of EI ferts do you think 15/3/15 would be a good target for NPK and .5 iron per week for CSM+B
 
nijat11 said:
I get GSA only on glass and AR mini. I tried to increase PO4 to 3 ppm and reduce iron dosage, did not help. Ended up just clean the glass often and cut leaves in a while. Also looking for a solution. All other plants are fine.
Click to expand...
3 ppm is not high enough. Try 7 ppm - that's what I do. I think GSA grows with mid-range phosphate (between 1 and 3 ppm) and less with either really low <1 ppm phosphate which plants won't like and also less with "high" >5 ppm phosphate.

Note that I add 7 ppm phosphate to Cambridgeshire tap water - I don't know the baseline tap water phosphate value.
 
dw1305 said:
Hi all,

Nerites (Clithon or Neritina spp.) <"will eat it">, they can crunch through quite hard surfaces to get at the chlorophyll. I associated GSA with hard, alkaline water, where these snails will be happy.

rockalgae-resize-jpg.77333


I didn't know that.

I think the problem with Chaetostoma spp. is that they have fairly specific habitat requirements <"PlanetCatfish.com - Chaetostoma formosae (Loricariidae) Cat-eLog"> which doesn't make them very suitable for most tanks.

cheers Darrel
Click to expand...
I have a lot of them, does not help at all.
 
Hi all,
nijat11 said:
I have a lot of them, does not help at all
Click to expand...
Shame, my water is too soft for them, so I've never kept them, I just got that they eat GSA from the internet......... . I think you need to give them a stern talking to and show them @Themuleous 's picture.

cheers Darrel
 
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