Originally Posted by Deathrow
And so does anyone know why sumps are in sections that the water flows either above or below. Why not straight through.
The different sections are for adding different stuff like your skimmer, return pumps, heaters etc. Some also have areas to create a refugium. Baffles (walls that are staggered at different heights) help to trap microbubbles before they get back to the main tank.
As for rock, I think 1kg equals 2.2ibs. Figure you'll need about 70ibs or about 32kg.
-Justin