16 July 2025
The effluent filter is a key component of your septic tank. It is generally recommended to clean it twice a year for a permanent residence, or once a year for a seasonal cottages, depending on use.
The effluent filter is a key component of your septic tank, installed at the tank’s outlet. It has been mandatory in Quebec since 2009 for all prefabricated septic tanks. Its main role is to trap larger particles and protect your onsite treatment system—such as those sold by Bionest—helping to extend the life of your entire septic installation.
Even when settling time is sufficient, solids can still be present in the effluent. This can happen due to disturbed particles, scum breakdown, or improper use of toilets (e.g. wipes, condoms, expired medications etc.). The filter stops these solids from reaching your treatment unit or disposal field.
Over time, as the filter captures solids, it can become partially or fully clogged, leading to several issues:
To avoid these problems, the effluent filter should be cleaned twice a year for permanent residences, or once a year for seasonal cottages, depending on use.
Cleaning the filter is straightforward, though not the most pleasant task. Wear long sleeves, pants, and rubber gloves. Open the second septic tank lid, grab the filter by its handle, and pull it out while staying directly over the opening. Be careful not to spill wastewater on the ground, as it may contain fecal bacteria.
Quickly move the filter over the first lid to avoid splashing, and spray it clean with a garden hose. Then return to the second lid and reinstall the filter, making sure to follow the directional arrows stamped on the unit.
When Bionest’s service team performs the required annual inspection, the technician will clean the filter for you—it’s included in Bionest’s service, unlike some competitors. If you have an advanced secondary treatment system, you’ll only need to do it once more during the year. For systems with disinfection, our technician will clean it during both of your annual visits.
