Yet another problem identification and remedy question

[sse450]

Hello Mates,

I am not sure if this is an alg or not? Some green spots (3mm-10mm diameter) appeared on the substrate 2 weeks ago. They are like paint stains on floor while painting a room. It doesn't seem like spreading (well this is how I observe at the moment).

Some info about the tank:
Tank setup is 1.5 month old.
70g
EI fertilization (started 10 days ago)
1/2 tsp KNO3 and 1/8 KH2PO4 as macro. 15ml JBL Ferropol every other day.
50% WC weekly
4x54watt (2xGrolux, 2x6500K fluorescent)
6hr/day photo-light period
30ppm pressurized CO2 by pH controller + CO2 reactor
Aquasoil Amazonia substrate
Plant biomass is pretty high
pH 6.0 (aquasoil lowers pH by itself to 7.0 from 8.1)
Eheim 2076 for filtration
Eheim Compact+ 3000 for circulation and driving CO2 reactor
9 SAE fish + some pest snails

Hint: I don't know if it is related but the spots appeared at the time when EI started.

I would appreciate any help.

Thank you.

 

[dw1305]

Hi all,

Some green spots (3mm-10mm diameter) appeared on the substrate 2 weeks ago

Judging by the colour it is Cyanobacteria.

I usually give the filter a clean, but as yours is a new set-up it may go away on its own as the tank matures.

cheers Darrel

 

[Greenfinger2]

Hi SSE, Nothing to worry about Just suck it up the pipe when doing your water changes Or if it starts to spread to quick do a few mini water changes sucking it out this should sort it out

 

[sse450]

Thank you verymuch.

I noticed that there are some gas bubbles attached to these green spots. Does it confirm that they are cyanobacteria?

If so, no need to use terramycine?

 

[Greenfinger2]

Hi SSE,
Does it look like this extreme Case I would do a water change and Suck it out now while there is only little bits of it. Better than resorting to chemicals to get rid of it

 

[dw1305]

Hi all,

I would do a water change and Suck it out now while there is only little bits of it.

Sounds a plan. Even if you can't see any BGA, if your tank water spells slightly "earthy" then there is some present.

If so, no need to use terramycine?

No.

Better than resorting to chemicals to get rid of it

It is also <"illegal in the UK">, and a lot of European countries to use antibiotics to treat Cyanobacteria.

cheers Darrel

 

[sse450]

Time to update.

As per your advises and other posts in the forum, I blacked out the tank for 3 full days (pitch black). After 3 days, to my surprise, all the cyanobacteria had gone without any visible trace. Just to make sure, I also treated the affected areas by hydrogene peroxide (3%). Then performed a 50% WC after a good floor cleaning. I also cleaned the filter thoroughly (yeah, without much consideration for the good nitrifying bacteria). So far, so good.

Thank you, Darrel and Greenfinger2, for encouraging me to use natural measures before resorting to chemicals.