| JBL ProCristal internal filters have a two or three-stage filter system offering the following advantages: The mechanical primary filter traps coarser particles such as fish excretions, plant residues, etc. and so protects the biological filter substance from unnecessary pollution. Long service life of the biological filter substance. Good degrading of toxic nitrogens such as ammonia and nitrite, as useful cleansing bacteria settle in the biological filter stage. |
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