Sparkling white sand

How does one go about having sparkling white sand. My sand doesn't seem to want to stay nice and white for more than 24 hours. After stirring and sifting the sand it will return with a coting of yellow greenish by the next day. My Glass by contrast doesn't need to be cleaned with the mag float for several weeks or more. I do run GFO in a reactor, and do use RO/DI water.

90g tank with 110 lbs live rock, with 30g sump and refugium with macro algae.

Thanks for any suggestions

 

Mine stays pristine, as do my rocks.

What exactly is growing on the sand? Diatoms? Cyrano-bacteria? What are your nutrient levels at? Light cycle? how many GPH of flow do you have?

Thanks.

 

What is growing on the sand is just as I described something yellow/greenish, I suppose it could be diatoms, but definitely not cyano. The rocks stay very clean. My return pump is a 990gph quiet one, I also have 2 koralia 1400 gph. I have maxspect mazzara led lights on at 50% intensity. My phosphates are 0.08ppm and nitrates 3-4ppm

 

Could you grab a picture? Is your return wide open? Even if it's at 50%, flow shouldn't be an issue.

Is this a new tank? If so, I'll guess diatoms. They'll go away once they use up the residual silicate. For now you can shirt some water over the sand with a baster. It'd be good to see a picture though.

 

I agree with fsukum if its a newer tank then it will just take some time. If an established tank then it may just be directing water flow a little but not to where it stirs your sand up. I have a couple of sand shifting star fish that seem to help keep thing stired up and a watchman goby to but then the goby can cause your rock work to shift with all there digging.