Activated carbon has many uses in a saltwater aquarium. But, how often should carbon be used and how often should it be changed? These and many more questions are answered about using activated carbon in your system.

More: DIY Carbon Tube Filtration Use Hiatt's Tri-Based Pelletized Carbon and Hiatt's Right Now! bacteria and end up with a fantastic biological filter as well as near zero nitrates.

Co-Current, Counter-Current, Needle Wheel, Venturi; it all sounds pretty complicated, but contrary to what some people would like you to believe, protein skimming ain't rocket science. Skimming is no more than injecting air bubbles into a water column, twirling them around for a bit, then skimming off the crud (proteins) that they collect. Exactly how different protein skimmers do this is a bit of an art, however. Here are the simple nuts and bolts of protein skimming. Understanding the principles makes it easier to find the right skimmer for your saltwater aquarium.

More: Top In/On Tank Protein Skimmers If you are planning to install a protein skimmer in or on your aquarium, these are the ones you will want to see. Compare Prices and save $$.

More: Top In/On Sump Protein Skimmers Compare prices on these state of the art sump mounted protein skimmers.

Some aquarists believe a QT is a waste of time and money, thinking that fish can stave off disease, parasites or infections on their own. Most experienced aquarists would disagree, having seen entire aquarium systems wiped out by the introduction of a new critter which brought a disease with it. You can decide for yourself if a QT is worth it.

More: Cheap, Easy DIY Quarantine Tanks. QT's don't need to be fancy or cost a lot of money, they just need to work.

More: DIY Aquariums are terrific Quarantine Tanks. Inexpensive, easy to build and they can be designed to any size you want.

The Dragon Eel is one of the rarest and most sought after eels in the world. Due to this eel's aggressive and predatory nature it is often difficult to keep with other marine life, including other eels.

More: Snowflake Moray Eel. A less expensive and safe alternative to the Dragon Eel?

More: Eel Photos Thinking about adding an Eel to your aquarium? Take a quick look at these Eels Photos to see what the possibilities are, especially the stunning Zebra Eel.

Photo © Keoki Stender