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Complete Filtration Systems

Centralised recirculating filtration systems, also known as RAS (recirculating aquaculture systems) and LSS (life support systems), are designed to deliver optimal, stable water parameters in order to promote healthy livestock. The overall concept has been developed over many years, through constant research and practical application. The concept is based on systematically filtering the water using a series of mechanical, biological and chemical processes before delivering each individual livestock tank with an independent supply of clear, UV-treated water.

Apart from a high level of animal success, each of our systems will achieve excellent levels of cosmetic acceptance, coupled with a low labour requirement, and they can be installed within a few hours. With the use of nitrifying bacteria cultures the biological filter matures faster and the system can be up to full capacity within 8-10 days (depending on temperature and stocking levels), three times faster than normal. 

The design of each system follows a series of disciplines controlling flow rates and filter capacities, proportioned to the biological demands, including eventual population fluctuations, that are typical of a wide range of commercial applications. Applications include marine and freshwater fish hatcheries and nurseries, research and development projects, shellfish depuration and specialist aquatic displays.

System packages have been designed with as much flexibility as possible. Modifications and expansions are easy to achieve according to your own specific requirements and application. 
The particular size and type of filtration package for a given application will depend on a number of factors including, but not limited to, the type of livestock being held, the total stocking density, the amount of food that is added to the system and the temperature of the water.  Please contact us if you would like to discuss your requirements in more detail, or complete our online enquiry form, and a member of our team will be in touch.

We are also able to design custom-built systems and supply individual components for those just looking to extend or upgrade an existing filtration system.

Recommended Accessories

  1. Fitted Battery Autowash Timer Valves for Protein Skimmer Wash Kits. 
  2. Ozone Generator with Redox Controller for use with Venturi Protein Skimmer. 
  3. Ozone Monitor or Ozone Controller for ozone leak detection (recommended for units over 2g).
  4. Titanium Heater with built-in digital thermostat. 
  5. UV By-pass for easy lamp changes. 
  6. Additional Reservoir for extra capacity. 
  7. Return water supply pump specified to suit flow and head requirements. 
  8. System controller for monitoring of water parameters, controlling ancillary equipment and alarm outputs.
  9. Additional mechanical filtration can be installed on the return pump for further removal of suspended solids. 
  10. Adaptaflex Rubber Tank Gaskets to connect supply pumps and drainage pipework into reservoir tanks. 
  11. Pipework and fittings for connecting to and from the livestock tanks.
  12. Replacement Mechanical Bag Filters, available in 50, 100, 200 and 400 micron sizes.

Complete Filtration Systems Technical Information

System Installation Tip 

  • Seal all threads into their respective ports using silicone aquarium sealer - this should be applied to male threads. 
  • All individual pieces of equipment must be fitted with socket unions. This will enable simple maintenance of equipment and make the removal or replacement of any individual component easy. 
  • Pump inlets should be positioned so that the water intake is made from the lowest point of the reservoir. This prevents the likelihood of any air being drawn into the water pump, as the pump will compress the air and water mixture and rapidly cause air embolisms in the fish. 
  • Bypass facilities should be fitted to UV sterilisers, cartridge filters and other similar equipment to facilitate ease of maintenance. 
  • All plumbing must be of pure grade plastics and of premium quality. We do not recommend the use of standard PVC or styrene for saltwater systems. If in doubt, please consult us.  All pipework and fittings in this catalogue are suitable for saltwater and freshwater use. 
  • Although installation time may be increased it often pays to install the system 'dry' to start with, i.e. without gluing, as this will help to overcome any layout problems and prevent wastage of components. 
  • During installation it is pertinent to remember that directional change of water through 90 bends and T's creates additional frictional loss, so care should be taken to minimise the number of such bends and wherever possible route water through T's directly rather than at 90.  
  • All joints must be cleaned with pipe cleaner before gluing and must not be stressed whilst wet, i.e. do not pull, bend or twist pipework until the cement is dry.
  • Plastic pipework will not support itself, so it should always be fixed to walls with the appropriate clips at recommended support intervals. 
  • When plumbing is finished it should be left for 24 hours before filling with water and testing

Commissioning a New System

After installation is complete the following procedure must be followed:

  1. Fill the system with water and turn on the pump. Care should be taken to make sure the pump has water in it first. 
  2. Check all joints and unions for leaks 
  3. Use this first water fill to wash out all the reservoirs, equipment and pipes. Remember to remove all traces of plastic swarf from pipe cutting and trimming. 
  4. Empty the system and refill with clean water.  Add 1 x 25kg sack of vacuum dried salt per 2000 litres and leave the system to run for 24 hours. This will help to 'cure' all plastic surfaces and remove any traces of oils used in the production of the equipment and pipework. 
  5. Empty the saltwater from the system and wash out with freshwater.  At this point it is a good idea to add any aggregate media being used (e.g. filter sand), after washing it thoroughly. 
  6. Once the system has been thoroughly washed out with clean water it can be re-filled.  If you intend to use artificial seawater, we recommend our Tropic Marin Synthetic Sea Salt.

Maintenance Tip

It is important that the system is properly maintained – it is after all the life support system for the livestock! Regular maintenance is crucial for any operation to be successful, both in terms of livestock success, and in the proper functioning and longevity of the system itself. Aside from daily visual system checks (we recommend a daily checklist is utilised – one is included in all Complete Filtration Systems Instructions Manuals), the following are the minimum recommendations for the successful long term running of a TMC Filtration System:

  • Wash bag filters twice a week and replace once a month. 
  • Wash cartridge filters once a week and replace once every six months. 
  • Do regular water changes to keep nitrate below 80mg/l (ppm). 
  • Change UV lamps and O-rings every 4000/8000 hours, depending on application. 
  • Change O-rings on pumps and sand filters once every 2 years.




System 10000


System 20000


System 2500


System 5000