Cyanobacteria Is Back, Please Help!

[keastclan]

Hi, I have an ongoing problem with cyanobacteria. I have a 180 litre tank with external filtration. I do 20% water changes twice a week.  I have previously treated this with 3 days blackouts, but unfortunately it returns.
 
I have read about doing a blackout and increasing the nitrates. Does this work? How would I do this?
 
The other thing I have read about is chemiclean. Does this work? Should I go down this route?
 
The more I read the more confused I get, should I buy something to increase the water flow certain areas too?
 
Very confused at the mo.......

 

[KirkyArcher]

Yes, adding potassium nitrate should help, http/www.seachem.com/Products/product_pages/FlourishNitrogen.html or drop your water changes to 15-20% once a week to help maintain nitrate levels at 20ppm, remove as much of the offending algae as possible manually, good water circulation is another big help in keeping BGA at bay

 

[keastclan]

how would you increase the water circulation?

 

[KirkyArcher]

You could remove filter floss if used, use nothing denser than medium foams, fit a spray bar, install a power head or small internal filter.

 

[Stimo]

i think these are good for water movement. can angle them anywhere which might be better than a power head
http/www.youtube.com/watch?v=MoyduoaNACo

 

[keastclan]

so would I angle something like that towards where the cyanobacteria currently grows? as I presume that is where I have dead water?
 
What I need is someone to come to my house and do it all for me lol

 

[KirkyArcher]

just start by trying to improve flow with your current filter, reduce water changes to build up nitrates and in the mean time reduce lights on time! and see how that goes for several weeks.

 

[Stimo]

so would I angle something like that towards where the cyanobacteria currently grows? as I presume that is where I have dead water?
 
What I need is someone to come to my house and do it all for me lol

 
yes basically or try moving your current setup around to try and eliminate the dead spot.
what are your lights on times?

 

[keastclan]

light on times at the moment are 2pm until 10pm, I can reduce that....
I've just moved one of the outlet heads to point down to see if that will create more of a current. It's a fluval that I have so the outlet is 2 heads on one pole in the right hand back corner

 

[DrRob]

Cyanobacteria, horrible stuff. As said, it thrives in light, high organic, low macronutrient environments. The nitrates themselves don't harm it as such but they do allow higher lifeforms like algae to outcompete it for the organics.
 
As Kirky said, keep the water changes down slightly if the replacement water is low in nitrates, but make sure you do keep things nicely clean. Clearing out clogged filters and making sure the substrate is clean are the other important things. As Kirky also said, filter floss is often the culprit for slowing filters and loads of trapped organics, so take it out for now.

 

[keastclan]

just cleaned the filter too. Doesn't look like there is filter floss in it, just sponge and substrate and the carbon (which I have now removed as the cloth bags it was in had disintegrated. How often should the filter be cleaned? and should there always be carbon in it?

 

[DrRob]

Filter should be cleaned when it's dirty, or the flow drops off.
 
Carbon is a complicated question, but essentially it doesn't need to be in there, although several people use if for a variety of good reasons, but it's worth knowing what it's doing if you're going to have it in there, rather than just hoping it'll help in some generic way.

 

[keastclan]

I think I am going to have to buy a wave maker looking at how my tanks is doing. No one told me that this hobby would be a bottomless money pit lol 

 

 
There is no way I can change how my tank is set up unfortunately

 

[keastclan]

does anyone have any idea what wavemaker I should get?

 

[DrRob]

Depends on budget.
 
Hydor are a well regarded make, things like vortech is money is no object.
 
All pond solutions do cheaper ones, although they tend to be larger and slightly less refined, but do give good bang for your buck.
 
Personally, I'd go for something like a hydor koralia, unless the budget was tight.