Do I stir the live sand?

True as you Dont want one if you have a DSB but like I said, if you have plenty of live rock or other bio filtration, your 2-3 inches of sand is not a dsb, the sand sifting star will eat everything INCLUDING detritus, algae, diatoms, AND bacteria but will keep your sand super clean.

 

Sand sifters are not detritus eaters. They eat spaghetti worms, pods, etc.

 

Either way, you want to get rid of "algae" or diatoms from your substrate and it will do it. However, every place that I have read where this invert has been for sale has stated that it also eats detritus
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BUT I personally HAVE NOT really seen it consuming detritus myself, because, well, i dont have detritus on my substrate so AZ may be right and the sites must be just advertising for sales. I dont know. Anyhow

Heres a thread on 3reef with sand sifters etc.
http://www.3reef.com/forums/sand/sand-sifting-species-profiles-cost-v-benefit-71312.html

 

ya the algae will just come, deplete the nutrients in the sand and go. id leave it.

 

SSS are predators, but I believe they are semi-omnivorous about it, eating the detritus, and even some algae, as well as the microfauna that is their primary target.

It is important to note that they do eat the critters that some people wish to have in their sand, and that deep sand beds need for optimal health.

DSB tanks probably should never have one of these, unless it's a really huge tank that the SSS can't really wipe out. And, even then, such an amount of sifting undermines some of the functionality of the sand bed, bringing more oxygen and circulation to the sand than is desirable.

Too many people seem unable to comprehend that a DSB is supposed to be "stagnant". That's healthy.