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The Difference Between Saltwater Filters And Freshwater Filters – Part 2


In the following article I share what I learned about The Difference Between Saltwater Filters And Freshwater Filters – Part 2. In the last post we discussed why it is not right to use a freshwater filter for a salt water fish tank. In this post, we will be discussing the three main filtration systems used in saltwater filters, which are Protein Skimming, Live Rock and Live Sand. I will refrain from making a recommendation on saltwater filters but I will be presenting the pros and cons of each so that you will be able to make a personal decision on which to use in your salt water fish tank.

The Difference Between Saltwater Filters And Freshwater Filters – Part 2

Saltwater Filters #1: Protein Skimmers

Protein Skimming is the process of removing any organic waste from the aquarium water before it even has the time to be broken down into ammonia. They do not break down the waste into any other forms. The way these saltwater filters function is by having the waste bond to bubbles inside the skimmer column and this is then removed into the skimmer’s collection cup. This way of filtering a salt water fish tank has a huge advantage over all the other ways, which is there is no end product such as nitrate.

Choosing the correct size protein skimmer for your salt water fish tank will prove very effective in removing any organic waste from the water, giving you the pleasure of a tank that has a very slow nitrate build up. The immediate removal of organic waste also stabilizes the alkalinity of the water, maintaining calcium levels and encourages the growth of coraline algae which are excellent in preventing the outbreak of hair algae and cynobacterias.

Then there is also the benefit of not having to do too many water changes. Having a good protein skimmer in your salt water fish tank reduces the need to change aquarium water too much, saving you big bucks on your water bill, not to mention the back ache that follows a water change. But even though it is very slow, nitrate and ammonia will eventually build up and this is the job of Live Rock and Live Sand.

Saltwater Filters #2:  Live Rock and Live Sand

Live Rock and Live Sand are natural biological saltwater filters. The way they function is by breaking down ammonia into nitrite, then nitrite into nitrate and finally nitrate into nitrogen gas. The major difference between conventional biological filters and these is the end product they produce. Biological filters produce nitrate which still needs to be removed from the water manually.

Live Sand and Live Rock produce nitrogen gas which leaves the aquarium naturally and is harmless to the aquatic life you have. When using Live Sand, it is recommended that you have a deep sand bed in order to maximize on the filtration that it produces. I must say here that Live Sand and especially Live Rock can be costly but in a future post, I will share with you some ways of saving up by “creating” your own Live Rock. So in summary, in my opinion well functioning saltwater filters for a healthy salt water fish tank will consist of a correct sized Protein Skimmer, Live Rock and Live Sand on a sand bed that’s 4″ to 6″ deep.

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