One & Only Nitrifying Bacteria for Freshwater Aquaria
One & Only Nitrifying Bacteria for Freshwater Aquaria
H2O-PURE One and Only Live Nitrifying Bacteria

One & Only Nitrifying Bacteria for Freshwater Aquaria

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The key to setting up a successful aquarium is to quickly convert the fish waste to a non-toxic form. This is done by nitrifying bacteria. Under normal conditions it can take 30 to 45 days for these bacteria to become naturally established in a newly set-up aquarium.

Unfortunately, during this time period, ammonia and nitrite can increase to levels toxic to fish a common problem called New Tank Syndrome. DrTim's One & Only Nitrifying Bacteria are the result of the latest scientific research and are used by public aquariums and professionals around the world to control ammonia and nitrite.

  • Eliminates new tank syndrome
  • Instantly creates a bio filter
  • Removes toxic ammonia and nitrite, naturally
  • No sulfur or other offensive odors
  • No wait needed
  • 100% natural

Use when setting up a new tank, after a water change, cleaning your filter, when adding new fish and after a disease treatment to control ammonia and nitrite.

Good for 6 months at room temperature, 1 year at 50F (10C).
Keep refrigerated for longest shelf life.

Directions for Use:
Minimum dose 10 ml per 10 gallons of aquarium water.
Cannot be overdosed.

Customer Reviews
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RatingMoney not wasted

3/25/2015 By: from Las Vegas Nevada.

I am not a big fan to writing reviews unless I come across a product that actually works. I am just a average Joe who wanted I small 5 gallon tank to put in my study. I had problems with the cycling process, probably because of the bio filter and tank size. This stuff works! Finally my ammonia levels are down and my fish seems more spirited.


2/11/2015 By: from Columbus, OH.

Pay attention to your pH, if you dip to 6.5 your nitrite will stay elevated during your cycle and it will take longer, not the fault of the product, this is just a "feature" of nitrobacter bacteria. Nitrosominas, the bacteria that convert ammonia to nitrate, seem ok. For all you CO2 injection freshwater plant people, this means keep your kH above 3 !

RatingIt worked!

1/22/2015 By: from MPLS.

I bought two 2oz bottles - one for my 30 gallon and one for a 10 gallon. I wanted to try a fishless cycle with the 30 gallon - as my 10 gallon will not (and still hasn't) cycle! I followed the fishless cycling advice and I cycled in 12 days!! My 10 gallon did not have the same results - but after reading advice given here - I think it is simply a fact of the tank being overstocked and it just can't cycle with that high a bio-load. Now the fish are in the 30 gallon and I will see if the 10 now cycles without the fish. *Oh - and like some others have mentioned - I had to double my dose of ammonia to even get it up to 2ppm. (60 drops - once it was 80 drops in my 30 gal) using the ammonia from Dr.Tims. **Plus - I live in a seriously cold place and my first order arrived frozen even with the winter packaging - bummer - but Dr. Tim's sent me immediate replacement via overnight shipping! Overall I am very pleased with the product and customer service I have received so far! I will come back again.

RatingBest Aquarium Products!

8/28/2014 By: from Florida.

I've used Dr. Tim's aquarium products for several years now. Thanks to the regular use of Dr. Tim's, I find it much easier to care for my fish. I don't need water changes (only adding water as necessary). Fish waste is broken down and the water levels remain excellent. Before using Dr. Tim's, I had a constant problem with maintaining safe levels for my fish and algae growth was a problem. I don't get algae growth anymore. You MUST use them weekly in order to maintain your aquarium. I wouldn't be without them!!

RatingThe invisible gift

8/14/2014 By: from louisville.

This stuff works great but you have to use it with that ammonia in a bottle or live fish it needs the ammonia to feed off of put this stuff in it stayed at 2 pm ammonia for like a week and then realized it needs more ammonia one I got the ammonia to 4 ppm it only took about 5 days to cycle the tank when the tank cycled did one more dose of ammonia one day later it was cycled and last night transferred my veiltail and my face gold fish to the new tank thanks Dr Tim

Previous Customer Reviews
Rating Really Suprised!!!
  Had just cycled a 50 gal tank and had 4 - 10 gal to cycle--and was not looking forward to it. Then I heard about "one and only", so I figured it was worth a try. Set up 4 10 gal and added One & Only as directed, and nervously watched if my fish made it. Checked each tank every day and was pleasantly surprised at the results. Would have no problem recommending it. Thanks Dr Tim.
  Reviewed by: Candie McCracken from Bogard, MO. on 10/27/2011
Rating Great Product
  I like many have been disapointed with bacteria in a bottle products in the past. I tested a few recently. This was the only one that definatly started working within 24 hours. Tanks were clear within 72 hours. I was using a fishless cycle at 85 degrees F.
  Reviewed by: Michael Roach from Ny State. on 9/5/2011
Rating Mr.
  Been trying to fishless cycle for a couple of weeks. Used a bottle of the One and Only and my cycle kicked in right away. Ammonia went to zero by the next day, NitItes spiked and went to zero after that. Worked as advertised.
  Reviewed by: Mike Corbett from Texas. on 7/22/2011
Rating I think it works
  I tried other products that claim to instantly cycle and they did nothing. I used this to speed up the cycle. I quickly got a Nitrite reading and in a few days, an increasing Nitrate level. Not 100% sure if it was the product or nature. Bottom line - it's worth a try!
  Reviewed by: Tracie Nicholson from Chicago. on 4/25/2011
Rating Wow. Works as advertised!
  Worked as advertised. Tank cycled in 3 or 4 days. added 3 fish a week for 3 weeks and tank is still doing great. 0 ammonia and still 0 nitrite!! Thanks Dr. Tim. Will definitely use it again.
  Reviewed by: david gilmore from Montgomery,AL. on 10/30/2011
Rating one&only
  you have to try it i use it to boost the biofilter after filter mant. YOU NEED TO TRY IT YOU WONT BE SORRY.
  Reviewed by: doug from smyrna,tn. on 9/22/2011
Rating one and only
  WOW!!! it works great well worth the money.I had trouble with ammonia not any more i plane to buy more ASAP!!!!
  Reviewed by: doug from on 7/11/2011
Rating Home Aquariast
  I read a lot online about the fishless cycle and was curious about trying it out. I read about the benefits of Dr. Tims One and Only and decided to give it a try on a new 60 gal. tank. I must say, I was not disappointed, 14 days later my tank was fully stocked full of beautiful fish. So far I am 4 days in and have not had any spikes in Ammonia or Nitrite. I am very impressed with the speed in which I was able to cycle my tank. Thanks so much for a great quality product.
  Reviewed by: Darryl from Buffalo, NY. on 5/15/2011
Rating Great Product!
  I just set up a system at my office. As I'm not the most patient person in the world, I wasn't excited about a 5-6 week cycling period. I used the product and in 2 weeks had a tank full of Africans and no new-tank issues. Great product!
  Reviewed by: Ned Little from Memphis, Tennessee. on 4/13/2011
Rating An excellent product!
  I'm a bacteriologist; so, I'm happy to be able to recommend this product because it always has worked very well for me. I think it's a good example of "truth-in-advertising," as long as it's stored for optimal stability in the refrigerator.
  Reviewed by: Arnold Kreger from Washington, DC. on 3/18/2011
Rating Does as promised
  I have used this product twice now when setting up my 125 gallon tanks. Both times I added a good number of fish the next day after adding and had no ammonia spikes in either tank. Thanks Dr Tim for producing a product that actually works as advertised.
  Robert Clifton, Colorado
Rating Dr. Tim's One and Only
  I did the fishless cycling with this product and in less than a week my 240g tank was completely cycled. Ammonia -0 Nitatres -20 Nitrites -0 Great product, will use again.
  Reviewed by: Shahlvah from Mesquite. TX. on 4/4/2012
Rating Fishless Cycle
  I started the cycle on my 125 gallon tank only 8 days ago. It is already cycled. Ammonia and Nitrite levels at 0.00 after about 20 hours the last 2 days. One and Only is exaclty what Dr. Tim said it would be and just as easy to use. They even sent Ammonia to use free of charge. I will use One and Only from now on.
  Reviewed by: Don from Colorado. on 2/10/2012
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