I had a 4in DSB in my 20g (high), it didnt look sloppy at all. I used natures ocean LS. It was white with specks of pink.
I kept it super clean with a tigertail cuke. (who I might add asexually reproduced in my tank!!! and then there were two.)
anyway, this kept my nitrates at 0. never rasied once in the two+ years i had my reef tank.
-oozy-