Dr. Tim's Aquatics One & Only Live Nitrifying Bacteria for Freshwater Aquariums, 4-fl oz bottle

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About This Item

Details

  • Prevents and eliminates new tank syndrome by instantly working to establish a biofilter in newly set up aquariums with 100% natural living nitrifiers
  • Controls ammonia and nitrite levels instantly by removing toxic ammonia and nitrite naturally in both freshwater and saltwater aquariums
  • No sulfide or other offensive odors so you don’t have worry about overusing
  • Once added to the tank, simply add fish right away!
  • Shake well before using and keep refrigerated for longest shelf life

Ingredients

Instructions

FAQ

Learn More About Dr. Tim's Aquatics From Our Team of Experts

Special Note
  • 2-oz bottle treats up to 30 gallons.
  • 4-oz bottle treats up to 60 gallons.
  • 8-oz bottle treats up to 120 gallons.

Questions & Answers

3 Customer Questions


can I use Dr. Tim's one and only freshwater for water changes?

Answer by ChewyJan 17, 2019
This live nitrifying bacteria is designed to be used during water changes, when setting up a new tank, or after a disease treatment.

how do you know if the bacteria is dead

Answer by ChewyMar 09, 2021
This product contains live species of ammonia- and nitrite-oxidizing bacteria that prefer to live in the fish tank environment.

is their copper in this

Answer by ChewySep 12, 2018
This product does not contain copper. This treatment contains 100% Live Nitrifying Bacteria for aquaria.
3.4
Rated 3.4 out of 5 stars
58 Ratings

43 Customer Reviews



Rated 5 out of 5 stars
By Miguel on Aug 6, 2025

This Product Actually Works

I used this in combination with Dr. Tim's Ammonium Chloride to cycle an aquarium (no livestock) filtration system. I dry started my planted tank and cycled the

I used this in combination with Dr. Tim's Ammonium Chloride to cycle an aquarium (no livestock) filtration system. I dry started my planted tank and cycled the filter unit separately since dry start is a 4 week process. I've tried other products in the past with limited success. This combination works IF you follow the directions for use carefully.


Rated 5 out of 5 stars
By Theresa on Oct 14, 2025

Dr. Tim's Aquatic Fresh Water Nitrifying Bacteria

I tried a small bottle from a specialty fish store, it was quite expensive. Was excited to find a better price and a bit larger bottle.

I tried a small bottle from a specialty fish store, it was quite expensive. Was excited to find a better price and a bit larger bottle.


Rated 1 out of 5 stars
By Rita on May 29, 2025

It didn't work

Don't understand how it can work for some and not for others. It absolutely did not work.

Don't understand how it can work for some and not for others. It absolutely did not work.


Rated 5 out of 5 stars
By devyn on Mar 25, 2025

It works

This is the only bacteria I have ever used that worked the way it was supposed to. Granted I triple dosed my systems to jumpstart the systems with fish in the t

This is the only bacteria I have ever used that worked the way it was supposed to. Granted I triple dosed my systems to jumpstart the systems with fish in the tanks


Rated 5 out of 5 stars
By Dez on Mar 21, 2024

The Best Beneficial Bacteria in a bottle on the market.

I've been using this product for the past 4 years and I always keep a bottle in the refrigerator just in case. It's the only product that works as the bacteria is

I've been using this product for the past 4 years and I always keep a bottle in the refrigerator just in case. It's the only product that works as the bacteria is kept cold in a dormant state until needed.


Rated 5 out of 5 stars
By Jacob on Nov 30, 2023

Best of the best!

Dr. Tim’s Aquatics One and Only is scientifically backed and proven to establish a robust biological filter when used as directed. Helped me deal with my persistent

Dr. Tim’s Aquatics One and Only is scientifically backed and proven to establish a robust biological filter when used as directed. Helped me deal with my persistent Nitrite issue because it is formulated with more bacteria that turn Nitrite into Nitrate.


Rated 5 out of 5 stars
By Buck on Jul 14, 2023

Works Great

I waited 2 and half weeks for my tank to cycle without adding beneficial bacteria. I added Dr. Tim's One and Only and had no ammonia in 24 hours and no nitrite within

I waited 2 and half weeks for my tank to cycle without adding beneficial bacteria. I added Dr. Tim's One and Only and had no ammonia in 24 hours and no nitrite within 72 hours. My tank had cycled within 72 hours of adding this product. I highly recommend it for new aquariums.


Rated 5 out of 5 stars
By Harvey on May 15, 2024

Bact

It works great

It works great


Rated 1 out of 5 stars
By Ogre on Dec 15, 2022

Not performing as expected

After 1 week and multiple additions of bacteria have seen no ammonia conversion. To nitrites and nitrates. No I have to spend more money on a different brand to

After 1 week and multiple additions of bacteria have seen no ammonia conversion. To nitrites and nitrates. No I have to spend more money on a different brand to try and get things rolling.


Rated 1 out of 5 stars
By Jonathan42896 on Apr 22, 2022

Useless product

I paired this with their bottle of ammonia and followed directions specifically. I've done fishless cycles before and never had this much of a problem while spending

I paired this with their bottle of ammonia and followed directions specifically. I've done fishless cycles before and never had this much of a problem while spending this much extra money.