Originally Posted by stevie8
What do you mean by a deep sand bed? How deep is deep? 6 inches? I afraid that will take up too much water volume from the sump unless I partition an area and divide the sump somewhere in the middle. How is this deep sand bed help in reducing nitrate? No water if flowing thru it? Sorry too many questions.
Im no marine keeper but ive done a fair bit of reading on the subject. DSB
are usually no more than 3 inches to help prevent gas buildup in the sand which can be harmful.
Usually a sump is already divided into sections and the sand goes into the refugium section along calepra and afew inverts like shrimp, snails, crabs. Also with a refugium in the sump you will need a light over the calepra on 24/7 forcing it to grow and helping absorb nitrates.
Heres a picture of a fully divided sump and lighting.
As you can see the water comes from the main tank to the right side of the sump where the protein skimer is located, it is then skimmed and passed through BioBalls where it then runs into the refugium, bubble trap then back to the main tank.
Refugiums are also good for having a safe place to grow copepods and other small inverts that fish feed off without their numbers dwindeling due to the fish eating them all. The Copepods are then whisked through the system and into the main tank for the fish to feed on. A good constant supply of natural food.