Fairly new to this hobbie and got couple questions I got a 50 gal dt and 30 g sump 1 third is a fuge with maybe 3 inches of sand some lr and chaeto wandering if anyone would kind of explain how it works I get the chaeto obsorbing nutrients but not sand or lr in it. Also if you could tell me if there is anything I should be doing to it ex.change sand cleaning etc.i have had it for a year and was already established. It's probably 4 or 5 years old all together I have never done anything to it.