i have a oceanic 75 gallon freshwater tank. and i am using a wet/dry sump. and was wonder if the bio-balls should be under water or should the balls be half way under water. you can look atteh pic and let me know if i have done it right. also is a overflow box nessiciary for my application. i have also been told to add a bio meadia filter under the bio- balls. anyone know why i would need that. i thought that was what teh balls were for. again this is a freshwater tank.
thanks for any help.