Dumb question

[Ekiel]

Does (months old) dessicated cyanobacteria recover when re-immersed in water?

[Squaffy]

Not a dumb question at all. Short answer is 'yes'.

Longer answer... Another way in which cyanobacteria are able to survive in extreme conditions is by producing akinetes, thick-walled cells that are able to resist desiccation (drying out) and freezing. They can remain dormant for long periods of time until conditions become right and they germinate (Clark, 1998)

[RTR]

+1 to Squaffy's post. A previously used but dried-out tank needs full breakdown and cleaning before re-setting. You need to rid of excess left-over organics and inorganics before re-setting and conditioning.

[Ekiel]

Is there any way to destroy cyanobacteria that have formed akinetes? I understand that spot treating with hydrogen peroxide works when the cyanobacteria is active in the tank, but will it work when they're dry?

[Pufferpunk]

Line the glass with newspaper-soaked acetic acid. It should easily scrape off after a few hours.

[Master of Puffers]

I'll second the vinegar...that stuff can shift a week's worth of assorted woodfire combustants with a quick wipe over.

[Squaffy]

I was going to suggest good old bleach if you're scrubbing out

PP - I was under the impression cyanobacteria produced acetic acid, do you have a reference point I could have a look at?

[Ekiel]

Actually, I have already scrubbed the tank, and it's been back up and running for a couple of months now without issue. What I'm really curious about is potentially cleaning the old sand and plastic plants that I couldn't quite clear the residue bacteria from with elbow grease.

[Pufferpunk]

I don't like bleach--prefer Oxiclean for that.

[Squaffy]

In the past i've cheated and used a Microbiology lab autoclave to sterilise sand (out of hours, hoping I didn't get caught) - you could do a home job in several parts if you have a pressure cooker, though not the plants, they'd melt - bleach for them, or Oxiclean as above

Edit to add... just digging through some old notes and it appears cyanobacteria are ubiquitous, as in they are everywhere, in the air, water etc. so it's nigh on impossible to get rid of them per se and their presence in a bloom will be entirely opportunistic, meaning water parameters containing excess nutrients for example.

Depending on how much time you have, you could put the plants and sand in water, add nutrients to get the cyanobacteria to grow, then zap it all with amoxicillin, but I personally wouldn't go to those lengths

[RTR]

I also have autoclaved substrates, but I don't have access anymore. Don't try that with porous rocks though....

BGA is opportunistic. Playing with (gentle current can squelch small invasions. Big or out-of-control infestations call for more drastic techniques.

I have used original OxiClean also and would again if I need a whole-tank decontamination. The simple OxiClean rinses free and non-toxically. There are no nasty residues.