Cyano on my sand?

[Turbosnail]

I think this is cyano on the substrate. Does anyone know why it is there? My readings are:
Ammonia 0
Nitrite 0
Nitrate 4-5
pH 8.4
I have been feeding sparingly twice a week. Lights are on about 10-11 hours a day.

My camera is really faded, so there is more than it looks like.
Thanks.

 

[kdogg85]

It sure is. How old is the tank? If you don't have corals, you can cut the lights to 2-6hrs a day. And a 30-40% pwc should help. If you have the test, check your phosphates, it is amazing what just a small amount can cause, phosphate, slow or no water movement, and the length of time the lights are on are the main factors for pest algae like this. Nitrate is as well, but those are the main 3 causes.

 

[Hinds04]

I would adjust powerheads a little and cut back on light... you should be able to feed every other day

 

[Turbosnail]

I do have some soft corals and anemones, so I can't reduce light much. I suppose what I will try is a phosphate test, reduce light to 9 hours for a bit, and a pwc.

Do you recommend a good brand of water mover? It is a 29 gallon tank. I have two petsmart brand powerheads and a biowheel filter. I don't like how the powerheads work though, I would rather have the ones that look like turbines (don't know what they are called though).

Thank you for responding.

 

[Turbosnail]

I would adjust powerheads a little and cut back on light... you should be able to feed every other day

I have been thinking that twice a week was too little. I will try every other day. Thanks.

 

[PrettyFishies]

Koralia by Hydor
Amazon.com: koralia

 

[Turbosnail]

Koralia by Hydor
Amazon.com: koralia

Hey thanks, that is exactly what I am looking for.

 

[David S]

are you using RO/DI water?

 

[austinsdad]

Start by reading this first.

Cyanobacteria, AKA Red Slime Algae

 

[Turbosnail]

are you using RO/DI water?

Yes

 

[Turbosnail]

Start by reading this first.

Cyanobacteria, AKA Red Slime Algae

Thanks, I just read the article. The only things that really apply would be the light cycle (10-11 hours) and phosphates(getting a test soon). I think water movement is adequate there are no dead spots. The water tests good (results in my first post), and I have been feeding very little. Also I do a 15-20% pwc every weekend. The sand it is growing on is a new addition(fine aragonite sand), could that be effecting anything?

 

[mr_X]

it's not water movement. i have had cyano grow right on the outputs of power heads. it's excessive nutrients. if your feeding isn't a lot, then your nutrient export is too little.

more flow is good to keep detritus suspended long enough for filtration to collect it, but the flow itself, or lack thereof is not it.

i also don't think it's too much light. i have seen tanks lit by sunlight and halides for a total of 12 hours a day and no cyano.

 

[Turbosnail]

It looks like it is time to get the skimmer fixed. And more water changes until then.

Thanks everyone for the help.