Fighting Cyanobacteria (bga) - Blackouts Work?

Hello
I have been battling cyanobacteria for the better part of two - three weeks in my 75 gallon planted. The tank is almost 4 months cycled. I believe the original incurision of it sprang from a low nitrate high organic debris environment with an inconsistent lighting schedule. Due to the scape there was a few rocks I wasn't moving previously to gravel vac and a large amount of detritus formed there. Since then I have been more diligent with removing said debris. Also purchased a timer to create a consistent photo-period (8hr photo period). As well as having a phosphate test kit arriving today to check a phosphate build up off the list (30-50% wc's weekly so I doubt it)

Equipment
75g freshwater tank
Emperor 400 & Sunsun 304b filtration
Air pump running 2 airstones (May begin turning these off in day time to promote better co2)
Low bioload

Stocking :
2 Honey Gouramis
1 Albino Paradise Gourami
3 Juvenile Angelfish
1 Clown Pleco
6 SterbaI Corys
Pest snail
1
I have negative Nitrate Creep with current plants

Parameter test results
Ammo - 0
nitrite - 0
nitrate - 10
- 7.2
- .25-.5
- 3° / 53.4
- 6° / 106.8



So onto my question / gameplan to battle it. Today I plan to peform some regular maintenance then initiate a blackout.

Parameteres check (ammo, no2 , no3 , phosp , gh, kh , ph)
Install timer (8 hour photo period)
Remove all easily accessible visible cyano via gravel vacuum as well as detritus.
Cut all lights - wrap front of tank in black trash bag to prevent ambient light (Plan to cut lights for 72hrs)

I have read mixed instructions on whether to dose macros (Potassium Nitrate) into the water column before initiating this blackout. From what I read Potassium Nitrate is supposed to help inhibit BGA growth due to it thriving in low oxegyn / nitrate environments. Potass I'm assuming is to help promote plant growth to out-compete the BGA.

After the 72 hours I will be doing another large WC / gravel vaccing to remove any build up during the period.

Any one have any suggestions on something I can do differently or an aspect I might be missing? If the 72 hour blackout fails I plan to use a product such as Chemi-Clean or Erythromycin (probably the former). Would rather avoid chemicals if possible though. Anyone have a positive or negative experience with these products?

 

All I can say is PLEASE work cause I have that nasty horrible stuff in 2 of my tanks as well. All I've managed is constant scraping it off and vacuuming. The one tank I compelty tore down twice but it's sand/ planted and it came back from that. Best of luck!

 

For sure its a pain wouldnt wish it on an enemy

 

Do you have a lot of fish in there? How are they doing? I was battling it a few years ago, and blackouts didn't work for me. I had fish die on me. I added something called blue exit and changed my lights (they were more than a year old) and I got rid of it. But if your lights are only 4 months old that shouldn't be it. Or did you buy a used tank perhaps?

Now I've got it again infesting a new 80 g tank. It's been cycled for a month. I think I got it from a guy I bought a fish from. I recognized the smell in his basement where the tanks were, but against better knowledge I bought the pretty little yellow pleco anyways. I've tried the blue exit again, but this time it didn't help. I think it started doing something, because the stuff was starting to fall off the plants and rocks, but after a water change it started coming back. I'll try one more treatment of it to see if it might do the trick, but I'm getting frustrated. One of the fish is getting a bit lethargic as well, so I'm getting worried

Keep us updated. Maybe you'll find the magic trick

 

It is a low bio load for the tank size, I am taking my time stocking it. Fish seem to be doing fine for the most part. Everyone is active and eating when fed. I've had some issues with a previous batch of corydoras from a lfs (one I no longer go to) having sudden die off crashing issues due to poor stock.

2 Honey Gouramis
1 Albino Paradise Gourami
3 Juvenile Angelfish
1 Clown Pleco
6 SterbaI Corys
Pest snail colony
1 Assassin snail
I have negative Nitrate Creep with current plants

 

Parameter test results
Ammo - 0
no2 nitrite - 0
no3 nitrate - 10
ph - 7.2
phosphate - .25-.5
KH - 3° / 53.4
GH - 6° / 106.8

Most levels show acceptable ranges afaik
So phosphate test shows no large build up and what I believe to be a normal range of KH/DH for the fish I am trying to keep.

 

I had the same issue in my previous tank there is a thing that I used that helps its called blue green algae remover from ultralife it does wonders

 

As an update : cyanobacteria is currently not visible. still small odor of it however.
It appears have alleviated, not sure if its totally eradicated.

Increased flow , nutrients , maintenance
Decreased light (now consistent photo period) , organic debris (better maint) , feeding

blackout ended friday and its now monday with no signs of the pest.

 

nice!! Here's hoping .