Dr.Tim’s One & Only Live Nitrifying Bacteria for saltwater tanks is widely used throughout the hobby and can be used to help prevent common issues with new tanks while helping stabilize existing tanks. Dr. Tim is considered to be one of the premier authorities on marine nitrifying bacteria in open and closed systems. One & Only contains millions of live nitrifying bacteria that will help quickly establish a biological filter in your aquarium allowing you to add fish almost immediately.

  • New Tanks
  • After Water Changes
  • Adding New Fish
  • After Treatments


Using Dr.Tim’s One & Only is very simple. You should first make sure that your tank is dechlorinated which is critical. If you do find the presence of chlorine, you will need to use a dechlorinator that does not contain aldehydes which can be harmful to the bacteria you will be adding. Turn off any protein skimmers or UV sterilizers and keep them off for up to 48 hours after the addition of One & Only Bacteria.

Shake the bottle very well; the liquid should not be clear. If the liquid is clear, you have more shaking to do! Pour the recommended dose directly onto your biological filter media for the best results. If you do not have a dedicated biofilter, you can just pour dose directly into your aquarium water.


For New Tanks

Add Dr.Tim’s One & Only to dechlorinated water after the aquarium has reached the proper temperature, and any filtration components are checked and functioning properly. Once One & Only is added to the tank, fish should be introduced within 24 hours. Without fish, no organic waste is generated, which the bacteria require. If you are not ready to add fish, you can add small amounts of ammonia to the water.

Temperature Sensitive – We recommend shipping Dr.Tim’s One & Only when outside temperatures range from 0°C to 25°C.

Refrigeration not required – Never freeze or store in temperature over 35°C – Stable for up to 6 months at room temperatures and up to 1 year at temperatures ranging 5°C to 10°C.



Instantly create a bio filter in saltwater aquariums that can eliminate new tank syndrome and remove toxic ammonia and nitrite without any sulfurs or odors.

Perfect for fishless cycling new aquariums.