Balancing My Aquarium


Apologies for the long / detailed message below. If you have the patience to work through I would more than appreciate the advice. I have an algae problem and my main question is what do I change next? Lighting (duration or intensity) or ferts?

I've had a 29 gallon running since 4th January and over the months I have been slowly increasing the amount of ferts and upgrading the lighting. Generally, the plants seem happy everything is growing and the water clarity has improved. Despite a heap of reading and a heap of dosing using Seachem Ferts I currently find myself with a zoo of algae (green spot, blue-green and black beard).

It's heavily planted. The plants in the tank include - Anubius, , WendtiI Tall (Crypt), Alternanthera reineckiI 'Mini' (could be redder), Amazon , monnierI (not happy), Blyxa japonica, Cyperus helferI (has Black Beard growing on it), Hydrocotyle tripartita Japan, Mayaca fluviatilis, Hygrophylia (sold name I think it is dwarf hygrophila) and .

The blue-green is on the surface in the roots of the Frogbit
The black beard is on the Cyperus HelferI and the drift wood
Green spot - was on the glass but now the dwarf hygrophila

Current parameters (night before 25% / 25 litre water change) are:
  • ph 7.1 (this has lifted recently (not sure why). I have amazonia substrate which buffers to 6.5 and I have been matching the change water to 6.5 with Seachem Acid and Alkaline Buffer)
  • NH 0; NO2 0; NO3 ~5
  • KH 3; GH 5
  • Phosphate 0
Targetting the values in Tom Barrs Non CO2 methods (). I'm dosing Seachem products on the Seachem planted aquarium dosing calendar using the EI Low Light Weekly (). Dosing:
  • Nitrogen 16mls per week
  • Phosphorous 20mls per week
  • Potassium 2mls per week (there is potassium in the other two Seachem macros)
I'm also using Flourish (4mls per week), Excel 3mls per day and Advance (6mls - 3 times weekly)
I am looking to switch to dry ferts and also considering iron - but trying to minimise the changes until I get this tank under control.

On seeing the phosphates at 0 - I have dosed to 0.5ppm and will test regularly for a while.

My lighting a Micmol LED (72 W at peak) is currently running between 11:00AM - 8:00PM (maximum or close is 5 hours). I was going to post the program but the text conversion of the table is a mess. I reduced the blue night lighting last week and the algae seems worse this week.

I think that is all. Goes without saying I'm keen to get this under control and your thoughts are appreciated. Cheers.


Giving this a bump up for you


Thank you Coradee - appreciated.


11am to 8pm is 9 hours of light. Did you recently switch to 5 hours? I'm wondering if your substrate is nutrient rich?


11am to 8pm is 9 hours of light. Did you recently switch to 5 hours? I'm wondering if your substrate is nutrient rich?

Thanks for your response - see attached is the lighting profile. The total wattage is the dotted line and then each of the channels is represented with a solid line. I was trying to indicate that there is 5 hours of a med-high (or close to max) lighting in the total photoperiod; the rest of the time is ramp up or ramp down.

There seems to be heaps of information on the lighting period but not so much on setting lighting programs. I am happy to shorten the photoperiod but I am also concerned that some of the plants would appreciate more light; specifically the monnierI (though it may be a nutrient deficit).

Do I shorten the total photoperiod but expand the 'max' period? Seeking the right balance in light that plants find useful vs light the algae finds useful. I also enjoy having the tank "low" lighted in the evening but I've stopped that in the last two weeks.

I've done some further research and read that splitting the photoperiod might be an option. Think I'll have a look at that.

The substrate is certainly nutrient rich - it is ADA Amazonia



  • 20180918 Lighting Profile.pdf
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I did more research on splitting the photoperiod and on balance have opted against it. Deciding to knock over one problem at a time:
1. black beard
2. blue green
3. thriving monnieri

I read this link -

Some of the science was a bit past me BUT key themes seemed to be
- dosing excel (no change required as currently dosing just above the recommended value daily)
- oxygen levels (have taken the airstone off the filter and will run 24 hours)
- water flow (can't address at the moment - unsure whether to add power head or upgrade filtration to over 10 times flow)
- lighting levels (have reduced the photoperiod by 1/2 hour to a total of 8.5 hours) - new lighting program attached.

Hopefully that reduces the BBA growth. To remove the existing BBA - I'm planning on trying a hydrogen peroxide solution to the driftwood on the weekend during the water change.

On a positive note - bought four otos and some red cherry shrimp over the week. Moved the cardinals to the QT and have let the otos / shrimp quarantine in the main tank where there is a food source. OMG the Otos are beautiful fish - useful, active (use the whole tank) and they play / tolerate each other (cardinals are more interesting in pecking order). Not sure the shrimp are in the tank - I can never find them in the planting.

I"ll keep updating this journey - Even though not a lot of responses - hopefully it will be useful (well will be when the problems are solved).



  • 20180410 Lighting Profile.pdf
    174.8 KB · Views: 46


Happy to report that I beat the Blue-Green algae (for now). Moved the frogbit to a container of old tank water during last weekends water change and gave the separate contained the 3 day black out treatment. I wasn't interested in treating the tank as I want to keep a food source for the Otos.

Well the frogbit has looked better - but there are enough signs of life that I know it'll come back and it grows so quickly. Importantly, there is no blue-green algae on the frogbit. Without the blue-green algae falling from the frogbit there aren't bits of it through the tank.

I did struggle with a diatom outbreak during the week. Made three changes (Pretty sure they all contributed to the outbreak) over the weekend:
- as above - moved the frogbit out of the tank (which is a nutrient sponge) and let a lot more light into the tank
- left the lights on too long on Saturday when I was making changes to the program
- introduced corydoras sterbaI which disturb the substrate and throwing all sorts of muck into the water column.

It was reducing daily but did a 50% mid week water change this morning - hopefully that brings the diatoms back under control - the water is a already a lot clearer.

On the list to dos:
- thinking instead of hydrogen peroxide I might take the driftwood out of the tank and hit it with boiling water
- seriously considering 1. upgrading my filtration for flow and pick up the disturbance from the Corys, 2. UV to reduce the spread of algae and 3. CO2 (the more I read the more it seems that fluctuating CO2 makes BBA thrive). To think the LFS suggested I only need another $100 for bits and pieces when I bought the aquarium kit.

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