Sand starting to turn brown
 

Basically my reef has been going for just over 6 months now. In the beggining I used to have diatoms on my sand until I got a yellow cheek sand sifting goby. Then everything was great my sand was white. I had to sell him 2 days ago since I have to downsize my and he wouldnt be comfortable in the smaller tank. Anyway in two days my sand is now getting brown again. Is there any way for me to get rid of the browning. I know I can stir it (prefer not to) or I can lower nutrients in the systems(however the system is mostly softies and they flourish in the nutrient full system) is there any other way to do it? Any type of small fish that would be ok in a 20 inch cube that could do it for me?

Thanks for the advice.

blue spotted gobies are good sifters and tend to stay quite small.(approx 3"). I had one in a 30 gal @ one time. upgraded the tank and then the goby.

Thanks. I will definitely look into it.

You could also try a strawberry conch. I have 2 in my 24 gal and they do a pretty good job.

would a conch be ok with my puffer? I mean my shrimps and big snails and hermits are ok. But conch are soft bodied arent they?

Conches have a hard shell and they're a fair size I would think it would be ok.