My sump is the same as well, first compartment filled with bio balls with a layer of white filter on top of it, 2nd compartment ceramic noodles, 3nd compartment more ceramic noodles 4th pump.
Also put an AC/DC air pump with stones in the 2nd and 3rd compartments if you have a power out for more than a few hours your boi will turn toxic, the pump will come back on when the power is back on and pump all the toxins into the tank.
Also put an AC/DC air pump with stones in the 2nd and 3rd compartments if you have a power out for more than a few hours your boi will turn toxic, the pump will come back on when the power is back on and pump all the toxins into the tank.