BioMech® Mechanical Filter Media


  • Non-Compacting
  • Ideal nitrifying bacteria bed
  • High Flow Rate
  • Permanent positive electronic charge
  • Features microscopic surface cavities
  • Suitable for aquariums and ponds
  • Suitable for freshwater and saltwater  

Kordon BioMech® filter rings are the most efficient biological and coarse mechanical filtration product for use in both aquaria and ponds. BioMech is a professional scientifically-developed product widely used in aquaculture and aquaristics world wide. It is particularly appropriate for high flow power filters, with either open or enclosed filter cartridges, because BioMech easily handles high water flow rates and resists clogging. The BioMech filter rings break up the water flow through the filter, preventing "channeling" or bypassing of the water around the filter materials.

BioMech provides excellent mechanical filtration, promotes extensive biological filtration, and enhances the effectiveness of subsequent filter materials.

Item No. 16608 - BIO-MECH® - 8 ounce jar

Item No. 16611 - BIO-MECH® - 26 ounce jar

Item No. 16695 - BIO-MECH® - 25 pound bulk bag

Directions For Use

In order to obtain maximum effectiveness in filtration, it is best not to mix Bio·Mech directly with other filter media. This allows the Bio·Mech filter rings to rotate under the effects of water flow and keep them from unduly clogging.

Fill the compartments with Bio·Mech to the level indicated in the instructions for the filter.

Fill the canister compartments as full as possible without compacting the Bio·Mech. The rings should be able to move freely and rotate in the filter compartments. Bio·Mech is normally used as the first layer of filter materials in contact with the water entering the filter compartments.

BIO·MECH filter rings seldom need cleaning, and when they do they are very easily and simply cleaned. They are reusable for many years. Despite BIO·MECH's ability to retain particles of debris, it usually rinses free during cleaning without much effort. Normally no special cleaning agents are needed except water itself. The most important consideration in cleaning BIO·MECH is whether or not it is important to keep the nitrifying bacteria alive that are on the surface and in the pores of the rings. If the bacteria are to be kept alive, the ideal way is to wash the rings in water from the aquarium or pond being filtered. This way will least disturb the bacteria. Since it may take 30 or more days for a new bacteria colony to become established, the BIO·MECH should be rinsed with water from the aquarium or pond it came from, or water as similar to it as possible. This method will allow the bacteria to remain viable and prevent dangerous concentrations of toxic ammonia and nitrite from occurring in the aquarium or pond after a cleaning of the Bio·Mech filter rings.
A good thorough rinsing is actually beneficial to the nitrifying bacteria because it assists them by removing their waste materials, since the bacteria cling tenaciously to the filter rings, Bio·Mech can be vigorously cleaned; even scrubbed (but no soap!), without markedly affecting the rings' biological filtering capacity. The important consideration is to change the temperature and chemistry of the water as little as possible (such as mineral composition of the water). Any appreciable difference in temperature or water chemistry can kill the bacteria.

If tap water must be used for the cleaning, it should be at the same temperature as the water being filtered. The washing should be done as rapidly as possible. Use Kordon's NovAqua® in the washing water to eliminate Chlorine and heavy metals from the tap water. Use Kordon's AmQuel® to remove chloramines and ammonia in the water. Use Kordon's Trans·CLEAR (for freshwater) or Kordon's SEA CLEAR (for saltwater) as a water clarifier to sweep bacteria and particles out of newly introduced water.

After washing in the original water or tap water, leave the rings wet, do not dry them, and return them to the water in the filter as quickly as practical.

If it is not important to keep the nitrifying bacteria on the Bio·Mech alive, the pressure-flow of heated tap water is usually all that is needed to remove all slime, dirt and excess bacteria. The sturdy long-lasting stoneware composition of Bio·Mech makes it resistant to cleaning agents. Biodegradable cleaning agents or chlorine bleach can be used if a more thorough cleaning is necessary. After cleaning, Bio·Mech should be well rinsed to remove cleaning agents that might be toxic to the water environment. Kordon's AmQuel can be used in the final rinse water to quickly remove traces of chlorine bleach (sodium hypochlorite) left from certain cleaning agents.

How it Works

KORDON BIO·MECH has proven extremely effective in promoting biological filtration, because it is an exceptionally good base for nitrifying bacteria. Constructed of a porous ceramic stoneware; Bio·Mech possesses a positive electronic change, so slight it is generally unnoticed, which attracts the nitrifying bacteria needed for biological filtration.

The open ring or "noodle" shape, combined with the porous nature of the stoneware, provide a tremendous surface area which can support a population of billions of bacteria in a relatively small filter compartment area. The colonization of Bio·Mech filter rings by nitrifying bacteria is extremely important to aquarium and pond keeping. These bacteria are beneficial in removing toxic ammonia and nitrite from the water. Biological filtration is the most effective natural way to remove these stressful and lethal substances from aquarium and pond water.

The extent of biological filtration is dependent upon the amount of dissolved oxygen available to the bacteria. Because the inlet area of a filter contains the highest level of dissolved oxygen, Bio·Mech is most effective when used in the inlet area or as a prefilter. The open design of Bio·Mech allows water to circulate throughout, bringing the necessary oxygen to the bacteria. The tendency of BIO·MECH to diffuse or spread water through the entire filter compartment is also useful, because this prevents "channeling" (water following the course of least resistance) and makes filter materials located in the subsequent water flow more effective. Bio·Mech resists clogging by slightly and continually rotating as the water flow passes through and around the rings. The ring shape gives Bio·Mech a major advantage over other filter materials such as those in pad or ball form, which do not freely rotate as they collect debris.

Bio·Mech is a very effective mechanical filtering material, especially in coarse screening. Mechanically the filter rings break up the water flow through the filter forcing the water flow to spread evenly without channeling or bypassing or clogging the filter materials. Bio·Mech rings regain and entrap large particles of debris which are worn down by water turbulence and bacterial action. The rotation of the Bio·Mech rings keeps the debris moving and prevents it from clogging the filter. The rotation also constantly changes the form and position of the debris, constantly moving it along the surfaces where the nitrifying bacteria consume the organic waste materials. By retaining larger debris particles within the Bio·Mech filter area, Bio·Mech helps all subsequent filter materials, such as finer mechanical screens, from becoming prematurely saturated or clogged.

The technical qualities of BIO·MECH that are important considerations in filtration are: 
  • durable, long lasting, reusable and easily maintained for biological and mechanical water filtration. 
  • easily sterilized and reused. 
  • high percentage of void space and low resistance to water flow (low pressure drop). 
  • irregular shape prevents packing. Its shape prevents locking of the filter materials together and reduction of water flow. 
  • large active surface exposed per unit volume (high surface area per cubic measure). 
  • good internal liquid distribution characteristics. 
  • suitably shaped to product turbulent contact between water phases. 
  • large number of interstitial transfer points per unit volume. 
  • microscopically porous surfaces make them a superior solid home for beneficial nitrifying bacteria.
Kordon Bio·Mech is durable, long lasting, and stable indefinitely. It requires no special handling procedures. Bio·Mech requires only a periodic rinsing to remain effective. Washing and treating with soap, household cleansers, and cleaning chemicals do not interfere with its electronic charge.

Bio·Mech does not affect, and is not affected by water quality, medications, or water conditioners. Bio·Mech is nontoxic and harmless to plants, fishes and invertebrates. This product is safe for use in all types of aquaria and ponds.


Bio·Mech is constructed of high-temperature-furnace-fired ceramic stoneware rings with hollow centers, approximately 7/16" (11 mm) in over all length and diameter. Each filter ring has approximately 1 square inch of outer surface area; 1 lb. of Bio·Mech contains about 300 filter rings, with 300 sq. inches of available outer surface area. These figures do not consider the microscopic small surface cavities and porosity of the ceramic material. There are about 10,000 Bio·Mech filter rings per cubic foot, with about 10,000 sq. inches of available outer surface area. The approximate weight per cubic foot of Bio·Mech is 55 lbs. Packed Bio·Mech has about 65% free space.

The ceramic surface has a permanent positive electronic change attractive to the gram-positive Nitrobacter and Nitrosomonas bacteria associated with biological filtration in water. The result is a tremendous potential for bacteria colonization. Bio·Mech is based on the original invention by Dr. Raschig, the renowned European water engineer, of the "Raschig Rings" which are used effectively in sewage and sludge water treatment in Europe.