Redearslider.com :: Filtration Overview

Quality filtration will not only help keep a healthier environment for your slider, but it will make cleaning less intensive. Filters capture the waste that is produced inside a tank and aid in the breakdown of potentially harmful materials. Filters vary in type, strength, shape, options and price. Choosing a filter that can adequately cycle your tank water efficiently is directly related to its effectiveness. Furthermore, a filter that is customizable leads to more options with the various filter media available. Turtles produce much more waste than fish would, so it is important to choose a stronger filter. Choosing the strength of a filter should depend on the amount of water you have in your setup. In most cases, the optimal preference would be that the filter is rated 3 times greater than the amount recommended for you aquarium size. For example, 50 gallons of water in a turtle tank should have a filter rated for a 150 gallon aquarium. The amount of water movement could be as high as approximately 600 gph (gallons per hour) for only 50 gallons of water.

A tank that houses more than one turtle or other inhabitants should have an even stronger filter. A second filter is an option worth considering on a large setup. Feeding outside of the tank in a separate container will assist in maintaining water quality. Less substrate will increase filter efficiency as well as placing the inlet and outlet at opposite ends of a tank. Regular water changes and filter maintenance are still necessary since not everything can be filtered out.

Make sure the manufacturers' directions are properly followed to provide maximum efficiency. Make an effort to understand the manufacturers' warnings to prevent injury and creating hazards. Filter attachments need to be firmly attached to prevent accidents, such as leaking. For hatchlings, make sure the inlet is not strong enough to trap them and that the outlet is not strong enough to impede their swimming and surfacing ability. In many filters, there is a switch to reduce the intake flow and you can use a prefilter on stronger canister and power filters. The outlet flow on many filters can also be adjusted and canister filters often come with different attachments or adjustable nozzles.

Types of filtration

There are 3 important aspects of water filtration to understand - mechanical, biological and chemical. These refer to the general efficiency and elimination of algae, debris, discoloration and toxic materials.

I. Mechanical

Mechanical filtration is the primary function of most filters. This media is inert and aids in the removal of visible debris and matter in your water. The foam pad that comes with a filter serves this function and needs to be regularly cleaned or replaced. Substrate and in-tank decorations can impede the water flow, which is critical to this type of filtration. Beneficial bacteria will develop on this media but are removed during cleaning.

Mechanical media is coarse and comes in various grades that refer to the size of the pores in the media. Very coarse media contain larger pores, which are designed to trap larger debris. Finer media can capture smaller particles though they will clog quicker and would require more frequent cleaning. Coarser media should always be placed before finer media in filters with multiple stages. A lack of filter maintenance will result in reduced efficiency and output.

II. Biological

Biological filtration is an important requirement of filters used with RES. Its main purpose is to breakdown ammonia, which can be toxic. Special inert media, such as ceramic rings and bio-balls, are a specially designed platform that encourages the build-up of beneficial nitrifying bacteria colonies. They expand the surface area for colonization and allow more oxygen and nutrients to be absorbed. This colonizing bacterium helps break down ammonia through nitrification (the nitrogen cycle). Waste and leftover food contribute to ammonia, which will be broken down into slightly less toxic nitrites. The nitrites are then broken down by another type of bacteria to form nitrates. These bacteria colonies take 4 to 6 weeks to develop and the filter needs to run continuously during this period. You could accelerate the cycle by using bio media from an established tank or purchasing concentrated forms of bacteria from an aquarium or pet store.

If your tank is occupied, you may want to monitor ammonia and nitrite levels while you are waiting for these bacterial colonies to develop. Well-oxygenated water also encourages nitrification and tap water should also be treated to remove chlorine and chloromines. When cleaning the bio media, it is best to rinse that media with existing tank water to preserve those colonies.

III. Chemical

Chemical filtration is specialized media that you can choose to help remove particular pollutants in your water. Activated carbon is commonly used to remove organic toxicants that might be present in the water after treatment. It might also remove medications from the water and should not be used during any treatment period. This is usually highly adsorbent media and binds to the unwanted materials, thus removing them from cycled water. Other chemical media are used to prevent algae, absorb ammonia, remove odors and adjust pH and hardness. Chemical filtration is usually not a priority for those with healthy turtles and access to good quality water. In many cases, partial water changes are more beneficial than using various types of chemical media.

Reference: http://www.drsfostersmith.com/pic/article.cfm?aid=215