Does I use Paradigm or Barrier?
This depends on the needs of the aquarium. If the water being detoxified is of very poor quality and contains large amounts of heavy metals, Barrier is suitable as it neutralizes them where Paradigm does not. If an additional stress and immune system boost is desired, Paradigm offers more in that area. Either conditioner is safe for aquaria and offers much to the health of the fish. Why not use both?