You might a well set-up a remote refugium for nitrate reducing plants, as they are more efficient than bacteria.
I've used planter boxes that hang off of the back of the tank for this purpose. The water exits the canister filter and travels through the planter media. The semi aquatic plants remove nitrate and the substrate fosters nitrifying and denitrifying bacteria. The canister is just a mechanical & chemical (carbon) pre-filter. Only wet the bottom 1/3 of the root zone.
Spathiphyllum (peace lilly), Aglaonema (silver queen), Philodendron, Anthurium, Dracaena (dragon plant), Cypress (papyrus) and Ivy are fast growers that consume a lot of nitrogen and phosphorus.