Dr. Tim's Aquatics One & Only Live Nitrifying Bacteria for Saltwater Aquariums, 2-fl oz bottle
Size:
Size:
Keep saving 5% on every order
Get deliveries on your schedule
Skip, change, or cancel anytime
No interest if paid in full in 6 months on PayPal purchases of $149+. .
About This Item
Details
- If used when setting up a new fish tank, it eliminates new tank syndrome.
- Instantly starts working to establish a biofilter in newly set up aquariums.
- Naturally removes toxic ammonia and nitrite.
- No sulfur or other offensive odors, 100% natural living nitrifiers.
- Fish can be added immediately after use, no need to wait!
Ingredients
100% Live Nitrifying Bacteria
Instructions
Shake well before using. Best to use the entire contents at one time. Minimum dose 10 ml (2 capfuls) per 10 gallons. Cannot be overdosed. For best results, turn off protein skimmer and ozone generator (if in use) for at least 6-8 hours upon application - overnight being the best. Filters socks should also be removed, if used, for the same period of time.
FAQ
One & Only Nitrifying Bacteria is the latest mixture of nitrifying bacteria by Dr Timothy Hovanec. There are formulations available for freshwater aquaria, saltwater aquaria, reef, nano, and seahorse aquaria, and koi ponds and water gardens. One & Only will quickly establish a functioning biological filter in your aquarium, allowing you to immediately add fish to your tank.
One & Only is designed for one job – to quickly establish a biofilter in your newly set-up aquarium so that your fish do not experience New Tank Syndrome (NTS), which is when the water contains such high levels of ammonia and/or nitrite that your fish die. One & Only does this by containing species of ammonia- and nitrite-oxidizing bacteria that prefer to live in the fish tank environment. One & Only is not a sludge buster nor will One & Only remove nitrate. One & Only will maintain ammonia and nitrite below toxic concentrations and establish a fully functioning biological filter in less than half the time of a similar but non-dosed aquarium.
Before adding One & Only to your tank, make sure the water has been dechlorinated. Research has shown that One & Only can be safely used with DrTim’s Aquatics’ AquaCleanse tapwater detoxifier. Other dechlorinators can be used but some are actually harmful to One & Only: do not use any product that contains aldehydes in its formula. UV-sterilizers and protein skimmers should be turned off before adding One & Only and remain off for 36-48 hours after dosing.It is important to shake the bottle well before adding One & Only. If you see only a clear liquid you have not shaken One & Only well enough. Pour the One & Only over the biological filter media in your biofilter. If you do not have dedicated filter media it is fine to pour the liquid into the fish tank water.
One & Only should be added after the tank has been set up. At this point the water should have reached the proper temperature and have been dechlorinated. Start the filter and make sure it is functioning and then add One & Only. Fish should be added within 24 hours of adding One & Only nitrifying bacteria. An alternative to adding fish is to add some ammonia to the water.
This is the hardest question to answer because every situation is different. One & Only will dramatically reduce the time it takes to establish a biofilter in your newly set-up aquarium. However, even One & Only has limits.For instance, if you set up a saltwater tank and use uncured live rock, One & Only may not be able to initially control the ammonia concentration in the water because there will be too much decay of organic matter from the uncured live rock.Or if you let every friend of your kids feed the new fish tank such that you are grossly overfeeding the tank, One & Only will not be able to maintain low levels of ammonia and nitrite.Also, some fish species are very sensitive to any amount of ammonia in the water so these fish should be added to the tank in the first 20 or so days after set-up.In general, you can add one giant danio-sized fish per gallon when initially dosing with One & Only. Feed normally and monitor ammonia and nitrite levels in the water. You might see a little ammonia or nitrite for a day or so but this will quickly disappear. You can then add more fish to the aquarium.
One & Only Nitrifying Bacteria is different than other bacterial mixes on the market today for a variety of reasons:• It is the only mixture currently available to the hobbyist that is grown and certified by Dr. Timothy A. Hovanec,• The ammonia- and nitrite-oxidizing bacteria in One & Only are grown together as a microbial community of bacteria which means they work together more effectively.• The bacteria in One & Only are grown on a microstructure, not as “free” cells in water, which helps the bacteria stay active for a longer time period.
No. One & Only should never be frozen, nor should it be kept at temperatures above 95°F. Normal room temperature will not harm the bacteria in One & Only. Perhaps it is easier to think about it this way: One & Only is not like an ice cream cone. Once ice cream is exposed to room temperatures it starts to melt, and if it completely melts you have a mess and no longer ice cream. One & Only is not like this. One & Only will last for 6 months at room temperatures (65 to 85°F). At colder temperatures (around 50°F) One & Only will last one year.
The best way to handle One & Only is to treat it the same way you would treat your fish. You wouldn’t keep the bag of fish you just bought at the fish store in direct sunlight in your car for hours while you continued shopping nor would you let that bag of fish freeze — the same goes for One & Only. Keep One & Only in moderate temperatures and it will be perfectly fine when you get it home and are ready to use it.
At a temperature of about 50°F, One & Only will be viable for one year. Each bottle is stamped on the back with the words “best used by” and then a month and year.
Use One & Only when setting up a new tank and after major environmental changes to your aquarium. Examples of major changes include a disease treatment with antibiotics or chemicals that are harmful to the nitrifying bacteria, after a major gravel cleaning which can disturb the bacteria on the gravel and after a failure of the filter.
Yes, but there is no real reason to do fishless cycling with One & Only. However, if you choose to go that route you need to add ammonia to the water after dosing the One & Only because the bacteria need some source of ammonia to start growing a bigger population. Dose ammonia to an initial concentration of 2 to 4 ppm which should disappear quickly, with nitrate increasing a little then disappearing. Dose one or two more times with ammonia and after your test kits show no ammonia and nitrite, it is safe to start adding fish.
The lot code is just a way for us to track the manufacturing and bottling process of One & Only. The lot number does not have a special code; it is just the lot assigned to the batch of One & Only bottled at that time. The “best used by” date is the date we recommend one uses One & Only by. It does not mean that One & Only will be totally ineffective after that date, only that the efficacy of One & Only will have decayed, but using One & Only will still establish a biofilter faster than doing nothing at all.
A common misconception about bacteria in general is that they die if they are not fed. From a human being point of view this sounds perfectly reasonable: if you don’t eat, you die. However, bacteria are not human beings. Bacteria operate much differently than people and have a variety of ways to deal with those times when resources are not available for them to grow and reproduce. Some bacteria when stressed (from say lack of nutrients) form spores and go into a resting stage, waiting for conditions to improve. Nitrifiers do not form spores but have other mechanisms to deal with nutrient deficient periods. For nitrifiers, one way to deal with stressful conditions is to form a protective “shield” called EPS. EPS stands for extracellular polymeric substances and is, in simplistic terms, an organic protective shield that research shows inhibits various organisms from attacking and breaking open the cell wall of nitrifiers. Nitrifiers belong to a very old line of bacteria (millions of years) and they have developed ways to cope with very long periods of “drought.” Because the nitrifiers in DrTim’s One & Only are grown on a substrate, they can form EPS when needed and last 6 to 12 months in a bottle.
The choice of whether to use the Freshwater One & Only or the Saltwater One & Only bacteria in a brackish water tank depends upon the salinity (or specific gravity [S.G.]) of your water.If your salinity is less than 10 ppt (1.007 S.G.) then use the freshwater formula.If your salinity is greater than 10 ppt (1.007 S.G.) then use the saltwater formula.

- 2-oz bottle treats up to 30 gallons.
- 4-oz bottle treats up to 60 gallons.
- 8-oz bottle treats up to 120 gallons.
Frequently bought together
- Dr. Tim's Aquatics Ammonium Chloride Solution for Cycling Aquariums, 2-fl oz bottleRated 4.6 out of 5 stars4.663Reviews$5.79 Chewy Price$5.79$7.99 List Price$7.99$5.50 Autoship Price$5.50Promo, New Customers Only: Spend $49+, Get $20 eGift Card
- Dr. Tim's Aquatics Ammonium Chloride Solution Aquarium Cleaner, 4-fl oz bottle$7.19 Chewy Price$7.19$8.99 List Price$8.99$6.83 Autoship Price$6.83Promo, New Customers Only: Spend $49+, Get $20 eGift Card
- SunGrow Refractometer for Saltwater Aquarium & Reef Tank, Koi Pond Water Salinity Meter TesterRated 4.5 out of 5 stars4.532Reviews$11.20 Chewy Price$11.20$16.99 List Price$16.99$10.64 Autoship Price$10.64Promo, New Customers Only: Spend $49+, Get $20 eGift Card
- CaribSea Ocean Direct Caribbean Live Aquarium Sand, 20-lb bagRated 4.1 out of 5 stars4.117Reviews$18.94 Chewy Price$18.94Promo, New Customers Only: Spend $49+, Get $20 eGift Card
- Instant Ocean Sea Salt for Aquariums, 160-galRated 4.7 out of 5 stars4.7404Reviews$59.97 Chewy Price$59.97$73.59 List Price$73.59$56.97 Autoship Price$56.97Promo, New Customers Only: Spend $49+, Get $20 eGift Card
- CaribSea Arag-Alive! Special Grade Reef Aquarium Sand, 20-lb bagRated 4.3 out of 5 stars4.338Reviews$25.76 Chewy Price$25.76$27.19 List Price$27.19Promo, New Customers Only: Spend $49+, Get $20 eGift Card
Questions & Answers
9 Customer Reviews
Best by date more than a year ago
We ordered Dr Tim’s Live Nitrifying Bacteria for Saltwater Aquariums from Chewy, expecting a quality product. The bottle is different than what we ordered, but
We ordered Dr Tim’s Live Nitrifying Bacteria for Saltwater Aquariums from Chewy, expecting a quality product. The bottle is different than what we ordered, but same product name and description. However the best by date is August 31, 2024. This was supposed to be live bacteria to help cycle our tank. Seems we spent $26 on dead bacteria. Quite disappointed in Chewy.
Expired Dr Tim’s
I received this bottle of Dr Tim’s one and only live nitrifying bacteria. The shipping was great and fast. But the bottle expired on August 31 2024. It was order
I received this bottle of Dr Tim’s one and only live nitrifying bacteria. The shipping was great and fast. But the bottle expired on August 31 2024. It was order on February 5th and I received it February 7th. I think I should be sent a new bottle that is actually within the expiration date because this is dead bacteria now and will not help my fish tanks.
Keeps sending expired bottles dead bacteria will not work.
I ordered and the first bottle I received had a best by date 06/30/23 I called they promised me a “inventory walk” to make sure the replacement would be a non expired
I ordered and the first bottle I received had a best by date 06/30/23 I called they promised me a “inventory walk” to make sure the replacement would be a non expired bottle. I received the replacement in a timely manner but it had the same best by date. At this point I’m just going to ask for a refund. The product is great as I have used it before I would just buy a non expired bottle elsewhere.
Dr. Tim’s
Did not do anything in my aquarium. Just clouded the water for a day. No form of movement after testing every day.
Did not do anything in my aquarium. Just clouded the water for a day. No form of movement after testing every day.
The real thing
After trying numerous bacteria additives with no luck. This product actually does what it says, and as usual Chewy shipped it quickly with the bacteria still alive
After trying numerous bacteria additives with no luck. This product actually does what it says, and as usual Chewy shipped it quickly with the bacteria still alive. Very impressed with your company. Thank you so much. Please stay safe and healthy
Dr Tim’s one and only
Wow works as instructed, tank ready in a week. Will use for now on when cycling a tank
Wow works as instructed, tank ready in a week. Will use for now on when cycling a tank
Dr.Tims One and Only
If you are doing a fishless cycle and you buy the Dr.Tims Ammonia Chloride the directions on the bottle say 4 drops per gallon, they are wrong, its one drop per
If you are doing a fishless cycle and you buy the Dr.Tims Ammonia Chloride the directions on the bottle say 4 drops per gallon, they are wrong, its one drop per gallon. I don't know how this could have happened but go to youtube and Dr.Tim explains how to do a fishless cycle.
Failed fishless cycle for a nano reef.
I bought a bottle of this product after talking to multiple other aquarists and doing research on Dr. Tims website. I was confident that this product would speed
I bought a bottle of this product after talking to multiple other aquarists and doing research on Dr. Tims website. I was confident that this product would speed up my cycle. After a few days after adding the product nothing had happened. I ended up buying a different product that worked perfectly. It may have been a bad bottle but have heard great things about this product. I was disappointed.
Doesn't Work
Rebuilt a 75 gallon aquarium in early September. Tried a fishless cycle but the tank had not cycled by 10/13 so I ordered a 8 oz bottle. It arrived on and was
Rebuilt a 75 gallon aquarium in early September. Tried a fishless cycle but the tank had not cycled by 10/13 so I ordered a 8 oz bottle. It arrived on and was added 10/14. Tank still had not cycled by 10/20 (ammonia levels still high). So another 8 oz bottle was ordered. It was delivered and added on 10/22. Aquarium still has high ammonia as I write this on 10/27. Nitrites are now high so something is happening. Whether it has anything to do with this additive, I don't know. But I do know that the claim that you can add fish right away is not true. Had I added any livestock to the aquarium, it no doubt would have been dead or dying. Certainly not worth the risk. Would not buy again or recommend.





