Cyanobacteria

[Up North]

I need help!  What is the best way to get rid of cyanobacteria?  It keeps coming back, I'm ready to take down this tank.  I just have a few fish in this tank that I can relocate if I need to.  I do have plants I would like to keep.  What are my options and what are the main causes of cayanobacteria?

Thanks

[Mmiller2001]

Spot dosing hydrogen peroxide wrecks it, and raise Nitrates to combat it. Improve flow throughout the tank as well.

[Up North]

Can I remove the fish and nuke the tank with peroxide?  If so how much per gallon and does it harm fish?

[PlaneFishGuy]

On 1/16/2023 at 6:11 AM, Up North said:

I need help!  What is the best way to get rid of cyanobacteria?  It keeps coming back, I'm ready to take down this tank.  I just have a few fish in this tank that I can relocate if I need to.  I do have plants I would like to keep.  What are my options and what are the main causes of cayanobacteria?

Thanks

@Up North What's the scale of the problem? Are you talking the entire tank of just a few areas that need cleaned up? 

I think with any bacteria or algae problem your prime suspect is going to be a light and nutrients imbalance.  I was able to eradicate most of my problem by dialing my lights way back  and getting the plants robust enough to outcompete stuff. My challenge was mostly blue/green spot algae on rocks and slow going Java fern. 

I would start with a minimalist approach before going to crazy....maybe dial back the lights, and address any excess nutrients. as @Mmiller2001 suggest spot dose some peroxide. I would imagine spot dosing Easy Carbon or Excell might work too. 

[Mmiller2001]

On 1/16/2023 at 10:29 AM, Up North said:

Can I remove the fish and nuke the tank with peroxide?  If so how much per gallon and does it harm fish?

No, just spot dose it and can repeat every 24 hours. Get a syringe and use 15ml per 10 gallons. Turn off everything pump wise. Spot dose it and let it sit for 15 minutes or so. Then pumps on. Repeat the next day.

Basically, paint across the worst areas.

Edited January 16, 2023 by Mmiller2001

[Up North]

I think I will try a different light, can't dim the current one.  I'm currently working out of state and I'm only home on Sundays so maintenance is slacking.  Maybe I try a blackout next week and give it a less powerful light after blackout

[Patrick_G]

On 1/16/2023 at 10:51 AM, Up North said:

I think I will try a different light, can't dim the current one.  I'm currently working out of state and I'm only home on Sundays so maintenance is slacking.  Maybe I try a blackout next week and give it a less powerful light after blackout

You can try putting some electrical tape over some of the LEDs. 
 
 

[Rube_Goldfish]

On 1/16/2023 at 1:51 PM, Up North said:

I think I will try a different light, can't dim the current one.  I'm currently working out of state and I'm only home on Sundays so maintenance is slacking.  Maybe I try a blackout next week and give it a less powerful light after blackout

Depending on the form factor of your light maybe you can raise it up away from the tank, either suspending it from the ceiling or propping it up on risers. That would effectively dim it.