20L Balcony pond - Cyanobacteria - Saving plants

amberz

New Member
Joined
20 Nov 2017
Messages
13
Location
uk
Not quite an aquarium, but kind of similar so thought I'd ask here. I have a 20L trough pond that I set up 2 years ago. It's been suffering with cyanobacteria during summer months. Last year it was the sheet type but this year it's really bad, with jelly like globs as well as the sheet type. When I set up the pond, I added garden stones that had moss on them and the moss has grown really well - some submerged and some emerged. I also have water mint. The plants are doing great but the water is awful! Even the snails didn't survive, so I'd like to break it down and start again. I think my error was adding an inch of untreated clay soil as a substrate.

My question is, will a bleach dip kill the moss? I'm hoping it won't kill the water mint. And most importantly, will it kill the cyanobacteria? An easier method could be to remove the stones with moss and the now trailing submerged growth and put them in shallow clear water to try and starve the cyano - anyone know if this would work?
 

jaypeecee

Member
Joined
21 Jan 2015
Messages
1,329
Location
Bracknell
Hi @amberz
An easier method could be to remove the stones with moss and the now trailing submerged growth and put them in shallow clear water to try and starve the cyano - anyone know if this would work?
I think this is the approach that I would take. Presumably, you could physically remove a lot of the cyanobacteria? This needs to be thought through to come up with a plan. Perhaps we can re-visit this tomorrow?

JPC
 

amberz

New Member
Joined
20 Nov 2017
Messages
13
Location
uk
Thanks for your reply. I have been trying to remove it, and last year I just about kept on top of it. I was thinking that after it's first year it would settle down. I added some European frogbit hoping it would block some light. It flowered and grows really well but this year it hasn't flowered and the cyano has been coating the underside of its leaves. Anyway, when this year did come around and the new species of jelly globs appeared as well, I realised the thing was getting worse, not better! The globs are easy to remove and I thought once removed they wouldn't come back, but they do. The sheet type comes back very quickly also. Because it's mostly emersed growth, the "pond" looks healthy, but of course when you look closely at the water - ug!
 

jaypeecee

Member
Joined
21 Jan 2015
Messages
1,329
Location
Bracknell
Hi @amberz

Let me say at the outset that I am not, by any stretch of the imagination, an expert on Cyanobacteria. I just happen to have taken an interest in them as they are such a potential menace in our tanks, etc. Now, with that caveat out of the way, it sounds like you may have both Oscillatoria (sheet) and Nostoc (gelatinous blobs) in your balcony pond. Please take a look at:

https://microbewiki.kenyon.edu/index.php/Oscillatoria

https://microbewiki.kenyon.edu/index.php/Nostoc

Dealing with these is not easy, as you probably know. I am aware of only two treatments for Cyanobacteria. I think one of these is an antibiotic and is therefore illegal to use in the UK. The other is something I've used with success on one of my tanks - but other people have not been successful when using it. May I suggest that you take a look at:

https://www.ukaps.org/forum/threads/cyanobacteria-identification-at-last.60496/

The above thread explains which treatment I used. Have a read and we can re-visit this a bit later today. That will also give other UKAPS members an opportunity to make their suggestions.

JPC
 

sparkyweasel

Member
Joined
30 Jun 2011
Messages
1,306
I would take the moss stones out and let the moss grow emersed for a few days; that should kill off the cyano on those.
And I would take some cuttings of the Water Mint, using the emersed growth; they would be a back-up in case the bleach kills the main plants. Then clean the trough out and start afresh.
With a bleach dip, it's a question of giving it long enough to kill the cyano but not long enough to kill the plants. Start with a short dip, maybe one minute; you can always do a longer one later if necessary, but if the first is too long you can't go back. :)
 
Top