Are these diatoms?

Hi,

I've seen all the threads about diatoms being natural when you first start a tank and so I've had some brown stuff starting on my substrate growing for about a week now which started growing during the tank's 5th week. I figured it was diatoms and I've been patiently waiting for it to burn itself out. However, today when I came home from work I noticed that it has begun bubbling up off the substrate, in one area it looks like a small mountain, bubbling 3 inches off the sand in the shape of a hill. Are these diatoms? Something else? I'm attaching a pic of one of the smaller colonies.

 

If you are talking about the red film, its cyano bacteria.

 

Yes I am, what should be done? My cleaning crew doesn't seem to be eating it, really. I know I have phosphate levels above normal, but I'm using only RO water now, so they should be coming down gradually.

Is cyano dangerous?

 

How many times are you feeding a day/week?
What kind of lights do you have?
How good is the circulation? (Powerheads)
What kind of filtration?
How old is the tank?
High phosphates will cause it to grow. I don't know of any CUC that do eat it, maybe somebody else knows of one.
Not dangerous to my knowledge, just ugly and really annoying.

 

Feeding maybe 5 days a week, but not much. 55 gallon tank with a Koralia 3 and a Koralia 2. 75 pounds of live rock. Tank is about 5 weeks old. Seems like the phosphates are the problem. I just read the ultimate algae thread. I'm going to try to siphon it out. I guess I'll keep doing this until phosphates are gone...shouldn't be putting more in now that I'm using RO (originally filled the tank up with tap).

 

5 weeks old? What in the world are you feeding that often thats in a tank that young?
Algaes are part of the cycling process.
How often are you doing water changes? How much?

 

I'm feeding a pinch of flake or a pinch of freeze-dried blood worms. Once a week I feed a pellet of krill. I have 3 blue damsels, one baby hippo tang, an algae blenny, an ocellaris clown and a fire shrimp. Corals: candy cane, toadstool, some mushrooms zooanthids and xenia.

I don't think the feeding is the trouble, it's the fact that I've had about 4ppm phosphate since filling it up with tap water. The cyano will die off once it consumes the phosphates, most likely, similar to diatoms, right?

 

OMG Thats WAAAY Too Much livestock for a 5 week old tank!!!
Reduce your feedings as that also aides algae growth. Go to maybe twice a week or so.

 

Also try getting a good skimmer. It will help get rid of some of the crud you unknowingly mucked your tank up with. Continue to vacuum the slime out.
Did you check to see if your cycle was over before dumping all of the critters in there?
What are the params?

 

Cycle was over, live rock was kept in this tank for a few years before I took it over with filtration. I guess the tank has been running for a few years, I just cleaned it up and took it over about 5 weeks ago, doing a large water change in the process, so the rock is old, tank is new. The nitrate, nitrite and NH4 are at 0. Calcium at 450, alk at 5 meq, pH 8.2. temp: 79 (as low as I can get it during this heat wave).