Started A Blackout

[keastclan]

I've got cyanobacteria and from what I have read on the forum I should try a blackout. So I have wrapped my tank in bin bags. Very nervous now, three days will be up on Xmas day afternoon, so another present to unwrap, just hope there are no nasty surprises. I did a water change just before and tested my levels which were fine, and have always been to be honest. 
The cyano was growing back quicker and quicker and I was at a loss as to what to do. 
Also yesterday had a death, One of my female platy's, (they always look permanently pregnant) looked like it had a uterine or rectal prolapse that area anyway, but just looked like fish flesh, not red just white, very strange. 
 
Wish me luck

 

[DoubleDutch]

Fingers crossed. I am not a fan of black outs though. Did you test Phosfates as well ?? Had Cyano-problems for years. They stopped after changing lights (which couldn't have done the job as I listen to experts) and adding ferts. Do you plants still grow or did they :"hit the break" as I think ??

 

[dave840f1]

Maracyn and Erythromycin both of them will cure your problem of BGA. Main cause of the outbreak is usually high Nitrogen and lighting of 530/620nm and 660/700nm so old worn out lighting on your tank can cause this problem.  Don't forget to clean out your filter thoroughly. Reduce your feeding of the fish for a while also reduces nutrients that feed the BGA.

 

[DoubleDutch]

Thoughts of causes en sollutions are sooooooooo different. I feed my fish lots and lots more than I used to when I had this bacteria. Adviced Waterchanges, less feeding didn't, total clean out, meds didn't solve this. Changing lights, adding ferts aso did !   

 

[keastclan]

I already add fertiliser, I have only had the tank since the start of May brand new, so I think it's unlikely to be the lights, the nitrogen level is fine, I test using a liquid water test kit made  by tetra. 
Unfortunately I can't just go and buy Erythromycin over here, I'm in the UK, will try this first and take it from there. Will also clean the filter thoroughly tonight (external filter). Talking of which, how often do people clean their filters?

 

[mark4785]

Sorry to contradict you Dave but cyanobacteria (or blue-green algae) is without a doubt caused by a low nitrate concentration of around 10-15 ppm (and apparently can also be induced by a dirty filter but I have no first hand experience of this claim). It is possible to get cyanobacteria in the lower substrate in a tank with a high nitrate level due to the build up of detritus but you would never see it expand above the substrate.
 
The OP has done the right thing in putting bin bags around the aquarium. I would recommend you triple wrap the tank with them as you don't want any light getting in there. Normally I would recommend not checking the contents of the tank during a blackout but as you have lost a fish just recently, I would recommend opening the lid and looking for any other fatalities. 
 
Blackouts are harmless to fish. Any fatalities will be the result of a disease rather than the blackout.
 
If you have a planted tank: I would recommend buying a nitrate testing kit and some nitrate fertiliser; use the latter to gradually increase your nitrate level to around 25 ppm and use the former to ensure you don't go beyond 25 ppm. This is a healthy nitrate concentration for both the fish and plants.
 
If you do not have a planted tank I recommend you don't place fertiliser in your tank and keep your nitrate level as low as possible (around 5 ppm) as without desirable plants to utilise the nitrate you will be feeding it to the algae. 

 

[DoubleDutch]

I already add fertiliser, I have only had the tank since the start of May brand new, so I think it's unlikely to be the lights, the nitrogen level is fine, I test using a liquid water test kit made  by tetra. 
Unfortunately I can't just go and buy Erythromycin over here, I'm in the UK, will try this first and take it from there. Will also clean the filter thoroughly tonight (external filter). Talking of which, how often do people clean their filters?

Please don't clean the filter too thoroughly. Otherwise you'll kill all the good bacteria as well and your tank will go into a cycle again !!!!
I only clean them a little when flow is getting less !!!!!
 
Overhere a low level of Phosfates is also believed to start Cyano, cause Phosfates are needed for plantgrowth as well in a specific ratio to nitrates. 
I believe 10 nitrates : 1 phosfates ??? Otherwise plantgrowth will hit the breaks again.
 
What lightbulbs are in BTW ? And how is plantgrowth ??
Think it's better to remove the source than to use meds (they never worked for me).

 

[dave840f1]

Mark if you read what I wrote you will see I did not mention NITRATES read again.

 

[keastclan]

Just to let everyone know, I unwrapped my tank. All fish were present and correct and all the cyanobacteria had gone. I would not hesitate to use this method again. My other good news on Xmas day is that I had vouchers for my LFS, yay!!!!