i have about an area of a sump 12 x24 x 12 and already have area for a dsb. id like to keep minimal to no rock up top. so im packing whatever have you in that two foot area. brands don't matter if ceramic has the most surface area thats fine, i just have about 10 gallons of bio balls and 200 lbs of lace rock i could tap into or buy ceramic rings, or whatever else.