purple ish algae ... how do i control this?

[atif]

Ok - over the past week this small ptach of dark purple algae is spreading ... is it dangerous or should i leave it alone to burn out. i only have 2 fish (clown and damsel) and the bio load is small (skimmer seems to be taking care of that). i only use ro/di.

thanks Atif

 

[steve-s]

If the water specs are up to par and the tank is not relatively new, I would suspect the types of food and/or amounts. Cyano can be fueled by many things but diatoms is primarily from silicates. Does the RO/DI have a HI-S filter and have you tested for SiO2 ?

Any new additions to the tank lately?

Cheers
Steve

 

[atif]

I get the ro/di from the LFS so I don't about the SiO2 content. No new additions to the tank. Water specs are a ok! I do feed the soft coral on plankton every other day - maybe I need to reduce this to every 3-4 days?

Atif

 

[steve-s]

The corals do not really need to be fed that often. Once or twice a week will be sufficient. Make sure as well you are feeding the right corals the right foods. Not all will consume zooplankton and may do better with phytoplankton instead. Once/if more fish are added, you will find these feeding less necessary. By feeding the fish, you will by default also be feeding some of the corals.

Although it is LFS water, I would still check it for purity. Some things you can test yourself, some you will need to get tested at the LFS, just don't tell them it's their own water.

Cheers
Steve

 

[atif]

Great point on getting them to test their own water ! I'm using phytoplankton to feed my corals ... I'll scale this back. I want to keep my tank as is for a few months before I add new fish. I stirred up the algae guck on my sand so that the filters can do there thing.

Thanks Steve.

 

[steve-s]

I would not recommend stirring these kinds of algaes into the water column. The cyano especially will just spread to other areas and become an even larger problem. If anything, syphon out the algae with a small airhose.

Cheers
Steve

 

[atif]

But this stuff is almost oily and stuck together. Can't really sypon it ... maybe I can peel it off the sandbed?

 

[steve-s]

The diatoms will not syphon out that well but the cyano should come off quite easily. Even if you take a bit of sand out with it that fine, it's easily replaced.

Don't concern yourself too much with the diatoms though. Once the silicates in the system are used up the algae will crash and die out on it's own. The cyano will not.

Cheers
Steve

 

[fishtender]

I fought a battle with cyano and won. If you take a small net and scoop up under the cyano then gently shake the net, the clean sand should fall throught he net and leave you with a clump of cyano that is easily dispossed of. This will not cure the problem but at least minimize it. You may have to do it often until you find the cause of the bacteria. Mine was a slight presence of Phosphates, (it soesn't take much), and the wrong lighting. I found that frozen brine has an incredible amount of Phosphates.

What seemed like a major battle then was merely a little inconvenience once I figured out the cure,(with a lot of help from my freinds here).

Good luck.

Howard

 

[atif]

Great advice ... I did scoop some in my net and will probably need to do it again soon. I'll check out my water quality this weekend.
Atif