Filtration

When it comes to any form of Aquarium one of the most important parts I think is the filtration well apart from the tank it self with marine even more so as many invertebrates and corals require very clean water to survive. The options out there can be confusing, canisters, hang on, internal and built in filters. Well all of these will have on of if not all three of the following types of filtration process included they just deliver these in there own way. 

Filtration types.

Mechanical:

This is usual the first stage offer by the use of sponges or foam pads. These catch the big bits of waste    things like left over food decade plants. With my current canister filters on my large cold water and tropical tanks I have three level of this filtration a coarse for the big bits, dense fine foam for the bits that are miss by the coarse then finally a very fine/polishing layer. I try create the cleanest water before it reaches the next stage which is the Chemical filtration in my canister filer however for my marine set up this will be different as I will be using the Berlin System which I will explain later.

Chemical filtration

Chemical filtration refers to any filtering substance that is designed to change the chemical composition of the water, but most often refers to the use of activated carbon or other cleaning resins. Activated carbon pulls dissolved organics from the water by adsorbing them.

There are also other products that fall under the heading of chemical filtration. Products like ammonia chips, designed to remove ammonia from the water. People who have excess nitratesmight use ammonia chips to slow nitrate production. Nitrates are not considered harmful in general, but an excess of nitrates is undesirable, particularly in salt water aquariums where nitrates must be kept very low.

Biological

This is is formed by bacteria with in the tank on sponges in the filter and if your using a canister from a ceramic or ceramic based media. This stage converts Ammonia through nitrite and nitrates then to nitrogen this is called the Nitrogen Cycle.

As the bacteria builds up on the sponges if you are using mechanical filters it is very important to only rinse these in waste water from your water changes as part of your maintenance if you use tap water or new reverse osmosis water to clean these sponges you can remove this layer and undo all the hard work of setting up the tank.

Berlin System

So I mentioned at the beginning that the set up I'm going to using the the Berlin System this this offers the best of the mechanical filtration through the use of a protein skimmer and Biological filtration through the use of Live rock and Live sand.

So what is a protein skimmer? its a form of mechanical filtration that only effectively works in marine aquariums by creating very tiny bubbles rising up a tube collecting pro tines as they rise. As the bubbles

reach the top of the tube the bubbles form a foam which then overflows in the a collection cup which is clean as part of your tank maintenance.

Proteins include ammonia, so an effective protein skimmer can also remove some ammonia before it breaks down in into Nitrites and Nitrate's both of which are unwanted in marine aquariums. The mechanical process helps alleviate some of the burden of the biological filtration provided live rock and sand with in the aquarium.

Tip when selecting a protein skimmer find one that can deal with twice the volume of your Aquarium and offers the best performance. With this in mind I may include extra funds for and upgrade for the one included in the kit I found.

Live rock this is a bit of a confusing concept to understand as we view rock not as a living thing but usually as a building material. Well Live rock is pieces of dead coral skeletons which have been harvested from coral reef areas. In the wild, live rock harbours both flora and fauna as well as beneficial (biological) bacteria. In an aquarium, if properly cured, live rock will continue to house both flora, fauna and bacteria.

Curing is the process of containing harvested live rock and allowing the dead and dying biological material which did not survive collection and shipping to decay. The dead material is then removed, leaving the surviving biological material on the rock. The curing process produces a great amount of toxins (ammonia, nitrite and nitrate) which are harmful to saltwater aquariums and their occupants. Thankfully your LFS or live rock supplier will normally do this for you. If this process is done correctly your live rock should over time come back to life with corals and invertebrates and the beneficial bacteria which helps with the bio logical.

Live sand, or LS is natural reef coral sand that is collected live from the ocean, or non-living coral sand that is cultured to make it live. What makes it live is the microscopic biological bacteria that grows on it, and the many tiny crustaceans and other micro and macro-organisms that reside in it. Live sand can serve as the main base for biological filtration in a saltwater aquarium, while the organisms help consume organic matter in the sand bed. Some of the organisms provide a natural food source for many aquarium inhabitants as well.
From reading about the Berlin system and users who have had these systems up and running for sometime 10 years or more with out major rebuilds actually improve rather than deteriorate as time passes.

  
I hope this has helped with little understanding on filtration if you would like more information I recommend The New Marine Aquarium by Michael S. Paletta.