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· Registered
2 Posts
Discussion Starter · #1 ·
I have two algae probs. The first is a black thread algae that covers most of the micro swords in the foreground. This is just beginning to appear. The second is a green fuzz on the drift wood and has been there since shortly after tank set up. See pics below. Any help on how to combat this stuff is appreciated.

Tank parameters as follows:

75 gallons
3.5 wpg, 9 hours/day (11-4, 5-9)
Pressurized CO2 (lots of pearling)
Ferts - Flourish, Seachem Potassium, Seachem Nitrogen, Fleet, Ferro Vit
NO3 = 5, PO4 =1
50% WC/week
Tank 3 months old

Thanks in advance for the help.


· Registered
54 Posts
Well your nitrates could be higher supposed to be around 10-20 ppm. Do you have good circulation in your tank? Also do you have a drop checker to let us know how much ppm of co2 you have just casue your plants are pearling doesn't mean you have enough co2. You may have enough co2 but bad circulation. Also just to let ya know the noon siesta is not necessary, but its up to you.

· Premium Member
8,540 Posts
Obviously your tank isn't in balance yet. Your stem plants look good. Are you EI dosing? I agree with Josh that you need more KNO3. Can you spot treat with Excel? Things are quite overrun with algae. You need to really start getting that stuff out of there. Since you have it in the grass I think Excell is your best bet. Do you have any amano shrimp and ottos? They will help eat it. I think you really need to up your CO2. What color is your drop checker. You need to start with it green and inch it up as far as your fish will let you. Cut your lights back a little to 8 or even 7 hours, until you can get this under control. Your other stems look great. Do you have enough water movement to move the CO2 around the tank?

· Registered
2 Posts
Discussion Starter · #4 ·
answers to your questions -

- circulation is good - especially in areas where i have probs
- i think co2 is about 30 ppm using the ph drop method (tap ph 7.6, tank ph 6.6). i have been told ph/kh method will not work for me since i use amazonia.
- i will eliminate the hour off for the lights during the day - i only had it to extend viewing at night. co2 is off during this time and that could be reducing co2 concentration build up.
- dosing three times per week with seachem ferts using fertilator as follows:
flourish - 5 ml
potassium - 12.5 ml (equals 6 ppm/week)
nitrogen - 10 ml (equals 7 ppm/week)
fleet - 1 ml (equals 1.4 ppm/week)
ferro vit - 10 ml (equals .1 ppm/week)
- there are 5 ottos on the tank, 10 large snails

i will increase the co2 and decrease the lights. my nitrates will probably increase on their own since i have recently increased the fish load. i will check nitrate levels and add enough to get to 10+ppm.

how do you spot treat with excel?

thanks again for the help.

· Registered
66 Posts
As a second check on the CO2 try taking a sample from the tank, not the tap, testing pH, letting the rest of the sample sit uncovered for 24 hrs or so then check it again. Give or take, a change of 1.0-ish indicates about 30 ppm. Again, like most other methods, this is only approximate.

· Registered
11 Posts
Unfortunately, I am not offering any solutions, just joining the club of algae growers and fighters.

Your advices are welcome - I have pretty much scanned the threads on solutions, applying some, but still suffering big time:

150x50x50cm, i.e. 375 L (100g), some 340L of water volume

Light: 4x80W T5 with individual reflectors, 2xGiesemann Midday + 2 x Sylvania GroLux, 10h/day. I have a glass top on the tank, which reduces the intensity to some extent.
Filtration: Tetratec 1200
Pressurised CO2, 5 bps, Ferplast diffusor. Dropchecker is green. C02 is on 24h/day, at night I turn on air pump.
Substrate: 1-3mm gravel + Tetra substrate, Dennerle tabs (Iron, nutriballs...)
1 600 L/h pump for circulation and water distribution
Water: pH 7, kH 8, GH 11
Medium plant and fish mass.
WC 2xweek 15%

PPS daily dosing Macro + Micro


I grow BBA, esp. on microswords, and in the part of the tank where there is the diffusor and increased water circulation. I used Easy Carbo before, but my HM does not like it at all, it basically turns transparent and dies, then it takes 2 weeks to recover. I understand BBA is related to CO2 level (being too small), but I don not understand it's strongest in the part of the tank where CO2 is at its peak. Interestingly, explosion occured when I dug up and removed some 20-30 cryptos, thereby disturbing the substrate substantially, as well as changed the direction of filter outflow pipe (to downwords)

2) GDA - it's on glass, and as usual, as soon as I wipe it off, it comes back again. Now I am growing it too, on advice I read here (Tom Barr recipe), now in week 2, before I remove it again once it has matured. What bugs me more then it being on glass is GDA on plants, esp. on Alternathera, and pretty much anything that's medium or slow growing. It managed to attach itself even on Ludwigia R. Rubin, which grows like weed (but not on HM or Micranthemum U).

My water parameters are all in check.

I reduced the light to 7 h/day, to slow it down - what I find as a paradox is that GDA likes high light, so according to some I should reduce it. On the other hand, most of my plants like high light as well, so if I reduce it even more, I can expect some plants to start slowly dying. I used to have T8 before, without reflectors, and with some species growing now I have failed miserably before.

Plants are pearling, but these algae are really pita. I am tempted to add some algicide, but this will be only short term solution. With lower lights (T8), without dosing macros, everything was OK, though slow growing, never had to clean the glass.

Your advice and guidance is highly appreciated.
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