While the turbos and the shrimp will aid in cleaning the tank of algae and detritus, they will not maintain the sandbed. The sand bed needs to be tended to... the sand fauna is what does that, they eat the fish waste, the detritus, leftover food etc...as well a turn the sand slowly. They are what makes the DSB
functional. A detrivore kit is simply an assortment of sand fauna to jump start your sand bed. They are available through www.inlandaquatics.com
they are a bit pricey and I would recommend inocculating with good LS
from an established DSB
, prior to purchasing one, but if you don't have any other options.... As for your 12yr old LS
, if it contains a decent amount of fauna, then you would't necessarilly need any of the other options, except to promote diversity in the sand bed.