Green algea on sand

[MaxerTheTaxer]

Here are a few pictures of the algea. I can't figure out what is causing it except for a Dragon sand siffter. Is it eating the bacteria that is healthy for the sandbed? It used to be on the rocks but I started using a turkey baster to clean the rock off (maybe once a month). I run a sump with a skimmer. A bag of Purigen and carbon rated at 100 gallons each and mechanical filtration. Although I am not a fan of mechanical filtration I use it from time to time (maybe once every 2 or 3 months). But I can't seem to get this algae on the sandbed to go away.

 

[morpheas]

@twilliard will probably be able to help identify this and maybe solve.

What are your water parameters? Any recent water tests you could share?

 

[mcarroll]

+1

How old is the tank as well?

 

[MaxerTheTaxer]

90 gallon display, 15 gallon sump, 150 gal rated skimmer, some sump algae. I use API test kit and everything is nearly undetectable by this kit. My tank is stocked with coral and fish. I haven't checked parameters in a while because after such a long time of testing and getting ideal water parameters im still having this problem. It seems to be my only problem. I thought maybe too much light because, based on its location, it gets direct morning sun. So I covered it up with a black drape for about 2 weeks only led light, With no success. It has been established at my new house for about a year. 2 years At my old house.

 

[MaxerTheTaxer]

When I blast the sand bed the algae breaks up easy. Easier than back in my begginer tank days when I used to have to scrub the rocks!

 

[saltyfilmfolks]

are you using Rodi water for top off and salt mixing?

Although I am not a fan of mechanical filtration I use it from time to time

Do you mean the skimmer?

Do you have a Phosphate test you could do?

 

[USMC4Life]

Is the tank near a window. Or is getting indirect sunlight?

 

[MaxerTheTaxer]

Mechanical as in cut to fit padding. The skimmer I do run 24/7. It works great! I do use RODI to top off. I just now did a test with api for nitrate and phos. Both came up at or near zero. It is hard to tell on the phos but if I had to choose it would defiantly be less than .25 ppm way closer to 0.0ppm.
I haven't done a watch change for about 2 months. But I have had this problem for about 8 months. And no matter what I seem to do it won't go away. I fed less, less light, large water changes, carbon and purigen.

 

[MaxerTheTaxer]

It get a lot of indirect sunlight. I tried to use a drape for the majority of the direct sunlight in the morning before my lights turn on.

 

[USMC4Life]

It get a lot of indirect sunlight. I tried to use a drape for the majority of the direct sunlight in the morning before my lights turn on.

That's it !

 

[MaxerTheTaxer]

That's it !

Dang I really didn't think that was it.