Red Algae or not??

[armymedic]

Can you tell me if this is Red Algae, it appears to be but not sure. if it is, how is it best treated? Is it expected in a new tank?

 

My photo period is 8 hours MH and 2 pre and post hours actinics.

 

Edited November 5, 2010 by armymedic

[dakotasreef]

Red slime algae. It is common to see in newer tanks or any tanks with excessive phosphates.

[astroboy]

What you have there is slime algae, I believe, which is not really an algae but a cyanobacteria. A search thru the forums here will turn up many discussions about it. My experience, for what its worth....

 

I had an underskimmed tank and after a few months I had a chronic problem with slime algae growing mostly on the sand bed. Alot of people will say that more current will remove it, or rather, prevent it from growing again, and there might be some validity to that, but it never worked for me. What I believe happened was that I had alot of organic material build up in the sandbed (4-6 inches deep) and that was hog heaven for cyanbacteria. It apparently needs some light or access to circulation since it never grew into the sand bed where the free lunch presumably was, but just stayed on the surface. The phosphates in my water were low, but the point I'm making here is that what's in your sand bed might take quite some time to diffuse into the tank water. The phosphate in the sand bed could have been quite high, I suppose...

 

When I tore down the tank the sand smelled bad, with alot of hydrogen sulfide odor, indicating alot of anaerobic activity. As I understand it, its the anaerobic bacteria that turn nitrates into nitrogen, but if your system is overwhelmed that doesn't happen and alot of nasty stuff accumulates in the anaerobic zone in your sandbed. From your picture I don't think your sandbed is deep enough for an anaerobic zone, but I'd imagine even a very shallow bed will accumulate organic material. When I set up my new tank 18 months ago I rinsed the sand extremely well for a long time and with a better skimmer I've never seen the slightest bit of slime algae.

 

(As an aside, I've had some very experienced aquarists tell me that you can over-skim your tank, the idea being that skimming removes alot of minerals that your tank needs, but I have to say I don't think I believe that. I have a Euroreef rated for 75 gallons on a 29 gallon tank and given how good those skimmers are I'd imagine if over skimming really existed I'd be having problems, especially since I'm a slug about water changes and run activated charcoal 24/7. I'd like to hear what people think about the existence of over skimming... )

 

One thing you can try is to siphon out the sand where the slime algae is growing, rinse it very well, and put it back. That always retarded the growth of the algae for a while for me, although after a while the organic stuff seemed to diffuse upwards and the algae would grow again (but not as much). Since you apparently have only a little algae in one spot, a localized siphon and rinse might be all you need. Its not something you want to be doing since it did seem to stress my corals, but none of them ever died, fortunately. A locallized siphon and rinse shouldn't do any harm.

 

In the long run, and I think everyone would agree to this, for some reason your tank has too much organic material. In my experience, it can take well over six months for a deep sandbed to clean itself with aggressive skimming and water changes. You might consider siphoning and rinsing or replacing all your sand if nothing else works.

 

I used antibiotics like Slime Away (I think that's its name) and while they did clean up the cyano for a while it grew back since the underlying problem was still there. I never had any problems with the antibiotics, supposedly it doesn't kill the good bacteria you need, but I don't recommend it. At best, its just a band aid.

Edited November 5, 2010 by astroboy

[zygote2k]

It's definitely cyanobacteria.

It's part of the new tank process. It should bloom then die off after a few days. If it doesn't, then you are either overfeeding or allowing too much nitrate to build up. If you haven't been doing water changes, now is the time to start. Weekly 10% works best for most. Try directing the current towards the spot where it grows. It tends to grow where current is slowest. Don't add red slime remover- you would be treating the symptom and not the cause of the problem.