View Full Version : Algae or Mould?

12-30-2014, 10:39 PM
Can anyone shed any light on a problem with my plants?

I have several Anacharis in the background of my tank hiding the heater element. It has developed a green slimy coating, slightly darker than the plant and mainly at the ends of the plants. The same slime is growing on my java fern and there are some small patches on the driftwood too.

I have cut back the Anacharis to remove the slime, removed any java fern that shows any signs of it and cleaned it off the driftwood but it keeps returning.

Should I be concerned about this? It doesn't look very nice but is it harmful?

Any advice on what it is and how to get rid of it would be appreciated.

12-30-2014, 11:03 PM
how long has your tank been set up? How long have the plants been in it?
any possibility you could post pictures?

12-31-2014, 08:11 AM
The tank has been set up for about 6 months. I started off with plastic plants but have been gradually replacing them. The anacharis has been growing for about 2 months and the java fern for a little longer.

I have been using Dennerle Plant Elixir fertiliser for a few weeks but the slime was there before I started using this.

I removed a great deal of the slime last night so there's not much to photograph at the moment. There may be a little bit left on the bog wood so I'll try to post a photo when I get home from work this evening.

12-31-2014, 02:09 PM
Is the slime hairy, like a hair algae? The only thing I can suggest is that it is algae and you may want to add some snails to help clean it up. Mystery snails would be the easiest, but nerite will do the best job as they love algae of all kinds. I see you have a pleco, but the clown eats more driftwood than algae. Do you notice the shrimp eating it at all? I have ghosts and I see they seem to prefer protein to algae.

12-31-2014, 03:48 PM
You might also have cyanobacteria

I would suggest googloing a few pics of it to see if that infact is what you have in your tank. Cyanobacteria takes a different approach to deal with as compaired to how you would deal with algae.

12-31-2014, 04:55 PM
It certainly looks the same as the cyanobacteria photos I looked at. There is none left after I cut back the plants so I can't post a photo. It came back after the last time I cut it out so no doubt it will again.

12-31-2014, 05:06 PM
I found this link on cyanobacteria


As well as this on a sticky under Algae in the forums located here;


Blue-green algae isn't algae at all; it's a photosynthetic bacteria. Cyanobacteria is also toxic to most fish and it also consumes Oxygen, meaning a full-blown invasion of Cyanobacteria can suffocate fish.
It's also a slimy, smelly thing and many people find it disgusting.
It almost always appears when the tank has either a short photo-period or low lighting.
The solution is simple, but counter-intuitive.

Increase your light. The more light you have the less likely you'll run into Cyanobacteria. If you lights are already bright, run them longer. If you have one or two 40-watt tubes, add another and run them 12 hours a day. Cyanobacteria is primitive enough it can't assimilate bright light.

Bright light and manual removal will beat Cyanobacteria every time. Thankfully, Cyanobacteria doesn't bind tightly with solid surfaces so siphoning usually gets most of it.

So if you run into Cyanobacteria in your tank, light it up and suck it up. May take some time to beat it totally, but it can be done.

Interestingly enough, Spirulina, present in many fish and people foods, is also a Cyanobacteria.

01-01-2015, 12:35 AM
Thanks for the information. The two sources suggest different treatments which is a bit confusing. One suggests no light for several weeks, along with other things, and the other suggests increasing the light. Does anyone have any experience of either of these treatments and which one works? I'd prefer to avoid antibiotics because I have baby & adult shrimps in the tank and this could be a problem for them.

01-01-2015, 12:54 AM
I had to deal with this twice. The first time extra cleanings and a lot (and I mean a lot) of extra waterchages did the trick, the second time I need to administer a single dose of antibiotics.

I would suggest to start with a lot of extra cleaning (to remove the cayanobacteria) and a lot of extra water changes to see if that will be enough to get rid of it.

01-01-2015, 11:14 AM
Looks like I have some work to do then, I'll keep you posted of any problems/success.
Happy new year to all my AC friends and thanks for all the advice over the past 6 months.

01-01-2015, 02:31 PM
Keep us up to date on your progress

01-04-2015, 09:38 PM
I finally managed to get a reasonable photo of the green slime and here it is...


Does this help with identification?

01-04-2015, 09:43 PM
Yup, that certainly looks like cyanobacteria to me

01-05-2015, 07:34 AM
Thanks Cliff, I'll keep up with the increased cleaning and water changes. Not an easy task with tiny creatures in the tank. I have accidentally hoovered up baby shrimps and cherry barbs during cleaning several times.

01-13-2015, 07:43 AM
I've been working hard on this problem and things seem to be improving. I'm still getting this nasty looking stuff but not in the same quantities. The extra cleaning and water changes are paying off, so hopefully I won't need any antibiotics. I have also changed the light bulb for one that is supposed to help, not sure if that is the case but it certainly makes the colours of the fish and shrimps stand out more.

01-13-2015, 12:57 PM
Good to hear you are making progress

What type of bulb did you just install ?

01-13-2015, 05:40 PM
The bulb is an 18" T8 from Interpet, called a Community Daylight bulb.
370 lumens and 6,000 kelvin colour temperature.

The previous bulb wasn't looking too healthy, clouded at one end so this is the replacement. Any advice on suitability would be appreciated.

01-13-2015, 05:50 PM
That one should work fine. The plants you mentioned before as pretty low demanding plants

01-13-2015, 06:55 PM
Thanks Cliff,

I'll keep up with the cleaning and water changes and see how things go.