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The Best Aquarium Bacteria Starters for 2022

best aquarium bacteria starter

The best aquarium bacteria starter will give your new aquarium a head start to become a healthy environment for your fish. You do not simply add fish to a tank full of freshwater (or new saltwater if you have a reef tank).

If you want to give your fish and the other organisms in your tank a better chance of survival, you should make the aquarium as close to their natural state as possible. This means you need to have colonies of beneficial bacteria already living in the water in the tank.

These bacteria will be responsible for keeping the nitrates and ammonia levels within the acceptable parameters. Bacteria will naturally grow in aquariums over time, but you can get them going much earlier using a good quality bacteria starter.

In this article, you will be learning all that you need to know regarding the aquarium bacteria starter. You will learn what qualities to look for and how to spot a problematic product.


Best Aquarium Bacteria Starter Reviews

1. API Quick Start Nitrifying Bacteria

api quick start nitrifying bacteria

This product can help significantly shorten the wait time between putting water into your new tank and then placing the fish into it. What used to take a couple of weeks to a month will become a week at the most. This product, in addition to ammonia, will quickly establish bacterial colonies in the tank and filters.

By the time your aquarium finishes cycling, you can put in the entire fish load all at once. You no longer have to start with a fraction of the total load at a time. This is nice for people like me with limited patience and who love instant gratification whenever possible.

Your aquarium will look just like how you want it to right off the bat when you use an aquarium beneficial bacteria starter. A properly cycled aquarium will increase the fishes’ chances of survival. It also makes it easier for them to thrive in their new environment. You will no longer need to lose around half of your fish stock before the tank stabilizes.

The best thing about this product is that even if it is a small bottle, it can still go a long way. You will only need a couple of teaspoons (depending on the size of your tank) whenever you start a new aquarium or need to make partial water changes.

The problem I had with it is that this alone will not be enough to cycle the water in the tank. You will need ammonia for the bacteria starter to jumpstart the cycling process, and new water does not contain any ammonia. You will need to add cycling ammonia to the water then add this product and water conditioner to get the process started.

  • Significantly shorter wait times before adding fish
  • Keeps the nitrates and ammonia well below the safe level
  • Increases the chances of your new fish thriving in the new tank
  • One bottle goes a long way
  • Comes in variants for freshwater and saltwater aquariums
  • Needs other components to get the bacteria growth started

Even though it is a bit misleading to say that you will only need this product to get your aquarium’s bacterial colonies started, it does help quite a lot. Once you get all the materials needed together, it will only be a matter of time before you can start populating your new aquarium.

2. Brightwell Aquatics MicroBacter7 Bacteria

brightwell aquatics microbacter7 bacteria

The bacteria needed for saltwater tanks are different from the ones for saltwater. It is the reason why you will need a different product for each. The nice thing about MicroBacter7 is that they make bacteria starters for both salt and freshwater. Be careful not to get them mixed up or else you will only end up killing the bacteria.

This best saltwater aquarium bacteria starter is essential for cycling new aquariums. You should not immediately put fish into a new aquarium. You have to cycle it first so that there are already enough bacteria to get the nitrogen cycle going. This product will jumpstart the said process. Instead of a month, you will only need to wait a week or so.

Aside from conditioning new aquariums, you can also use it to revive your somewhat neglected tank. If your fish seems to be swimming in their waste and the filters are not much help, do a partial water change and use this product. I have done this a couple of times and it worked out quite well every time.

My reef tank used to have a problem with cyanobacteria. It got so bad that I used to lose at least one fish a day. Thankfully, after using this product, the population of essential bacteria skyrocketed, thereby eliminating all the cyanobacteria. Now, my reef tank looks much better than it did before.

The only slightly negative comment I have with this freshwater and saltwater bacteria starter is that it works significantly slower than other brands. Other bacteria starters I used only took a week max before they cycle an aquarium. This one took at least two weeks to cycle completely.

  • Comes in freshwater and saltwater variants
  • Effective for cycling new aquariums
  • Can help improve the condition of neglected tanks
  • Easy to use
  • Helps control and even eliminate non-beneficial bacteria
  • Slower-acting compared to other similar products

This product may not work quite as fast as the other bacteria starters, but at least, it does increase the likelihood of your fish and other organisms thriving in their new tank environment.

3. Tetra SafeStart Cycles New Aquariums

tetra safestart cycles new aquariums

This product is one of the fastest working bacteria starters I have used so far. The instructions indicate that I can put fish immediately after I pour the entire bottle into my 50-gallon tank. However, I decided to play it safe and waited until the next day. Not only did my fish survive but they are now also thriving in their new environment.

I did a couple of tests and I found that this product is one of the fastest that cycles aquariums. I found that the bacteria contained in the product already started doing their job, which is reducing ammonia and nitrates, the following day. This does not mean that the product eliminated all the toxins but it did make a dent.

Here is another thing that I liked a lot about this product. It does not need any additional ammonia to start working. You just need to pour the product into the tank water and it will immediately get to work. In just a week, sometimes even sooner, your aquarium will be fully cycled and ready to receive fish.

If you have a tank with nitrate and ammonia levels that are a bit on the dangerous side, you can use this to stabilize the aquarium hopefully on time. I had one tank with an ammonium level that would not go down, so I bit the bullet and used half a bottle of this product. After a couple of days, my tank finally cycled.

While other bacteria starters only need a couple of teaspoons to kickstart the cycling process, this one requires that you pour in the entire bottle. You are buying a single-use product. This is not much of an issue. However, if you are used to using other brands, then pouring an entire bottle into your aquarium may seem shocking.

  • Starts working in as fast as 24 hours
  • Among the fastest to cycle new aquariums
  • Works on its own – You do not need additional ammonia
  • Works fast to lower ammonia and nitrates
  • Can supposedly make an aquarium safe for fish right after application
  • You will need to use the entire bottle for a new aquarium

Although it might seem wasteful to use an entire bottle of this product on a new tank, keep in mind that this is necessary to get the cultured bacteria to thrive quickly in the water.

4. MicrobeLift NiteOut II

microbelift niteout ii

One of my aquarium-keeper friends recommended this product when I mentioned that I had trouble getting the nitrates under control. I am happy to report that it worked as advertised. In just a couple of days after using a bit of this product, the ammonia and nitrate levels plunged to zero. They stayed that way until today.

The bacteria contained in this product are quite robust. They can quickly populate even a large aquarium in just a short time. In addition, once the aquarium has a healthy bacteria population, it will ensure that the ammonia and nitrates are always under control.

Another nice thing that I liked about this product is that it relies on a completely natural process to get the nitrates and ammonia levels down to zero. This product does not contain any harsh chemicals that might harm your fish.

One of the best things about having a properly cycled aquarium is that the bacteria will take care of most of the solid waste left behind by your fish. This means that your aquarium filter will not fill up as quickly. With that said, you do not have to replace filter elements quite as often.

The only complaint that I have is that this product should at least come in a smaller container. The 16oz bottle is more than enough for dozens of 100L tanks, so if you are not planning to reset your tanks around 40 times within the next year, then you will be wasting the remaining contents of the bottle.

  • Quickly reduces the nitrate and ammonia levels
  • Does not contain any chemicals
  • Promotes healthy nitrate cycles in aquariums
  • Helps lessen the amount of organic waste the filter needs to remove
  • Once cycled, the bacteria will ensure proper nitrate and ammonia levels
  • The product does not come in a smaller bottle

This product is ideal for beginners as it is quite easy to use. It is also almost foolproof. However, you will be getting much more product than you will ever need, so you might want to share the remainder with your aquarist friends before the beneficial bacteria expire.

5. Dr. Tim’s Aquatics One Only Nitrifying Bacteria

dr. tim's aquatics one only nitrifying bacteria

This product is one of the quickest-acting best reef starter bacteria starters I have tested. It only took around two days before the bacteria were able to start reducing nitrates and ammonia significantly. After two weeks, the aquarium is already properly cycled and ready for the fish stock.

The instructions state that you need to use the entire bottle starter bacteria for the aquarium on the same day that you open it. The reason is that the bacteria suspended in the product will start to die.

If you want to make it last for a couple more months, then you should place it in the refrigerator. On the other hand, you can pour the entire bottle into your aquarium. Do not worry as you cannot overdose your aquarium on this.

Aside from getting rid of ammonia and nitrates, beneficial bacteria can also fight against the bad kinds of bacteria that can make your fish sick. One of the most common and toxic bacteria that could grow in your aquarium is cyanobacteria. You can deal with them easily if your aquarium is full of beneficial bacteria.

This product is completely natural, too. There are no artificial chemicals or any other additives. The only things that are in the bottle are water and bacterial culture. This is the reason why you need to use up the bottle if possible once you break the seal.

The only problem that I had with this fish tank bacteria starter is regarding shipping. I live in the south where the summers can be quite brutal. I made the mistake of ordering a bottle of bacteria starter during the middle of the summer. When the package arrived, it did not work at all because all of the bacteria died in the heat.

  • Quickly cycles new saltwater tanks
  • No chance of overdosing
  • Can also get rid of bad bacteria
  • Completely natural as it does not contain artificial ingredients
  • Easy to use
  • Needs to be kept in a cool storage space, which causes some problems in shipping to areas that frequently have a hot weather

This is an important component that should always be present when you are starting a new saltwater aquarium. Yes, your aquarium may cycle on its own, but going down this route can be hit-or-miss.

If you are okay with losing a couple of fish while waiting for your tank to stabilize then you can do without this, but I suppose you do not want that to happen.

6. Fritz Aquatics 80209 FritzZyme 7 Nitrifying Bacteria

fritz aquatics 80209 fritzzyme 7 nitrifying bacteria

Ammonia and nitrates will start rising much earlier than when the bacteria that are supposed to keep them at bay get a chance to establish themselves in the aquarium. This product gives the good bacteria head-start so they can get rid of the ammonia and nitrates as they come.

This bacteria starter contains balanced amounts of beneficial bacteria and not just one kind. This gives this bacteria starter the edge over other brands that contain just one strain. It is this combination of nitrifying bacteria that makes them more efficient at dealing with ammonia and nitrates.

This product is not just for newly set up aquariums. You can also use it on those that already contain live fish. If your aquarium suddenly gets a nitrate spike, you can use the product to get it under control before your fish start dying one by one.

It also works well for bolstering the effectiveness of your filter system. Once you seed bacteria in the filter system, this will enable it to also deal with ammonia and nitrates in the water. You can also add a bit of this product when you are planning to add more fish into your tank.

The only problem I had is that it takes a significantly longer time to get the aquarium cycled. This is most likely due to the product containing several types of bacteria. Your aquarium will still cycle, but you need to be a bit more patient when using it.

  • Gives the nitrifying bacteria a head-start to get established
  • Contains a balanced amount of bacteria strains
  • Ideal for use on new tanks or on aquariums that already contain fish
  • Helps fortify filter systems
  • It takes a longer time to cycle in an aquarium

Although this product takes a longer time to cycle, once the bacteria establish themselves, they will keep the ammonia and nitrates at perfectly safe levels. This particular strain of bacteria is quite efficient at its job.

7. Ecological Laboratories Microbe-Lift Bacteria

ecological laboratories microbe-lift bacteria

Aside from using this to get a new aquarium to nitrate cycle, I also like how effective the product is in dealing with sudden and unexpected ammonia and nitrate spikes. This product might not work as fast as nitrate and ammonia removers, but it will not stress the fish and other organisms in the tank.

If you have tried everything you can think of to get rid of that slightly fishy smell coming from your aquarium, then you need to check this product out. Not only does the bacteria contained in this product help deal with ammonia, but it can also help get rid of the smells coming from the water.

Another benefit of using this product is that it helps the filtration system do its job. Aside from helping the bacteria break down the waste left behind by the fishes, they also offer aid in consuming the extra protein in the water. This ensures that the protein skimmer will also have a lighter load.

As mentioned earlier, the bacteria in this product help break down the solid waste from the fish. These include not just the ones that fall under the substrate, but also the small pieces suspended in the water. This means that the water in the aquarium will always be clear.

I only have one complaint and that is the fact that the contents of the bottle smell horrible, like a bunch of rotting eggs. This is due to the ammonia that helps get the bacteria started. Don’t worry, though. The smell does dissipate almost immediately after you pour the product into the water.

  • Drastically reduces ammonia and nitrate levels
  • Removes odors and reduces the need for water changes
  • Helps fortify the filtration system
  • Keeps the water clear
  • Improves the nutrient uptake of plants and corals
  • The product smells bad

This bacteria starter is among the best that I have used over the years. It works great for starting new aquariums and treating existing ones with ammonia and nitrate problems. Many aquarium owners highly recommend this product, so you should at least give it a try.

8. ATM Aquarium Colony Nitrifying Bacteria

atm aquarium colony nitrifying bacteria

This bacteria starter contains Nitrococcus and Nitrosococcus strains that are some of the best options when it comes to nitrifying ammonia and nitrates. These bacteria strains are the reason why this starter product is one of the best that you can buy right now.

The bacteria in this product establish themselves quite fast and get to work almost immediately. The instructions state that you can place fish inside the tank the same day that you used this product. Just to be on the safe side, I waited an entire day before testing the water, and I was pleasantly surprised that it had almost finished cycling.

This marine bacteria starter contains all-natural ingredients. There are no artificial ingredients or harsh chemicals. This means that it will not have any adverse effects on the coral and live rock that you may have in your reef tank. This is especially important if you spent hundreds or thousands of dollars on your corals.

The bacteria contained in this product are so efficient at their job that they can help improve the performance of the filtration system. The filters do not need to deal with solid waste as the bacteria will start to break them down almost immediately.

The bacteria also consume the excess protein in the water. This means that the protein skimmer does not need to work quite as hard.

The only issue that I have with this product is that it has a very short shelf life once opened. You cannot use it as a maintenance product as the bacteria will only last a couple of days or weeks depending on the climate. It is advisable to use the entire bottle in one application.

  • Contains excellent bacteria strains
  • Works quicker than most other bacteria starters
  • Does not affect coral and live rock
  • Helps the filtration system work more efficiently
  • Same product used by many commercial aquariums
  • Does not have a long shelf life once opened

This product came from the same people who were in the hit Discovery Channel show, Tanked. ATM is, first and foremost, a trusted brand in the custom aquarium-making industry before they got a TV deal. With that, you can be sure that their products are legitimate. This bacteria starter lives up to the hype and more.

9. GlasGarten Bacter AE

glasgarten bacter ae

If you like to keep freshwater shrimp, snails, and other invertebrates, this product will help create the ideal environment for them. It contains essential bacteria that will treat the water so that it could be in the best condition for your freshwater shrimp. It encourages the formation of microfilm on all surfaces underwater.

The microfilm produced by this product serves as a food source for shrimp fry, which encourages them to grow and thrive in the tank environment. In addition, since the adult shrimp will have a lot of food sources, they will not be tempted to cannibalize their own young.

This product is a self-starting one. In other words, you do not need to use other products to get this one to work. You just have to scoop out the right amount using the included scooper and then sprinkle it into the water. The powder will start to react with the water upon contact and it will start spreading immediately.

Just as you saw, this product is quite easy to use. You do not have to mix the powder with anything else. If you do not have that many shrimps in your tank, you can simply halve the amount instructed. You can use this several times a day or more depending on how voracious your shrimp eats.

As mentioned earlier, you might want to consider rereading the instructions for using this product. The amount stated in the instructions is too much, and would only end up getting suspended in the water. It is best to do small batches and then scale up if you notice that your shrimps are not getting enough.

  • Creates an ideal environment for shrimp and other freshwater invertebrates
  • Greatly increases the chances of shrimp fry to survive and thrive
  • Does not require other products to work
  • Easy to use
  • Has an impressively long shelf life
  • Kind of confusing instructions that may cause you to use too much of the product

Use this product sparingly and not as often as mentioned in the directions for use. In any case, it works as it promises it would and more. If you like keeping freshwater shrimp, then you may want to give this product a try.

10. Aqueon Pure Bacteria

aqueon pure bacteria

Unlike other bacteria starters, you do not need to measure the amount needed to dose your aquarium. This product is inside individual gel balls with one ball required per 10 gallons of water. So, if you have a 30-gallon tank, then you need to throw in 3 gel balls.

Also, unlike other bacteria starters, you do not necessarily need to use all of the products once you open the package. I wanted to cycle a new tank (50-gallon), so there were still 7 orbs left. I kept the remaining orbs 211on the bottom shelf of my fridge, and I used them over the next couple of months as maintenance doses.

The bacteria contained in these gel balls are quite fantastic at what they do. There are times when my protein skimmer would have a bad day, leading to the water getting a bit cloudy. It has never happened yet since I started using the product several months ago.

Another nice thing about using it is that it is impossible to overdose. You can throw all of the orbs into your tank without worrying about it causing any adverse effects on the fish. On the other hand, doing so will not speed up the cycling process. All that you will be doing is wasting money.

I have no complaints about how this product works, but what I did not like is that they can be potentially dangerous when used on a tank with fish. When the gel balls hit the water, they will start to melt, though not that fast. I lost two cichlids because they choked on these orbs.

If you plan to use it for maintenance, throw it into the box filter instead.

  • Easy dosing, no measuring required
  • Easy to store with a longer shelf life
  • Can help maintain clear water
  • Not prone to overdosing
  • Safe to use on all freshwater aquariums
  • If you have big fish, they might swallow the gel ball and choke on it

Although it will take a bit more caution on your part when using this product, it is, no doubt, more convenient than other similar products. If you want an effective bacteria starter, that is also convenient to use and can be stored for months, then you should check it out.

What to Look For When Buying a Aquarium Bacteria Starter

best beneficial bacteria for freshwater aquarium

Here are some of the features and qualities that you need to keep an eye out for when you are shopping for a bacteria starter for your new aquarium:

How Fast it Works

Normally, it would take a couple of months before an aquarium can cycle on its own, which I do not recommend that you do. On the other hand, the average bacteria starter can take around three to four weeks before it cycles the water in the aquarium.

That said, you should forgo placing fish inside the tank for at least a month. Some products promise that your aquarium is properly cycled in less than a week. Some brands do hold their end of the bargain, but others do not work as fast as they claim they do.

For beginners, it is best that they stick to the not-so-fast acting bacteria starter just to be on the safe side and always check the ammonia and nitrate levels.

How Efficiently the Bacteria Work

Not all nitrifying bacteria work as well as the other. However, since you have no way to test bacteria starters first before purchasing, you can browse user reviews instead.

Check out what other people are saying about the product that you are interested in and see if they are happy with their purchase. Odds are that you’ll feel the same way.

Ease of Use

Some bacteria starters only require that you measure out the right amount and then mix it into the aquarium water. Some brands require that you also place a bit of ammonia into the water to get the bacteria started.


The cost will be purely subjective. If you cannot afford a product, then you should look for the next best thing that fits within your budget. If you cannot afford a product that sells for over one hundred dollars, then check out the ones that are less than $50 a bottle.

Frequently Asked Questions

best saltwater aquarium bacteria starter

How do you Introduce Good Bacteria to an Aquarium?

The old way of introducing beneficial bacteria into a new aquarium is to put some water from an already established one. Now, you can find bacteria starter products that already contain good bacteria strains.

The good thing about them is that you know exactly what kind of bacteria you’re dealing with. You just need to pour a designated amount of the bacteria starter into a new aquarium, and then wait until the water cycles.

Which Starter Bacteria are the Best for FRESHWATER aquariums?

In my opinion, the best beneficial bacteria for a freshwater aquarium are nitroso coccus (which converts ammonia to nitrites) and nitro coccus (which converts nitrites to nitrates). You can usually find these bacteria in the top brand bacteria starters like the one sold by APT.


Although an aquarium can naturally cycle itself, it will take months. In addition, you stand to lose fish before it finishes. To make your aquarium a healthy environment from the get-go, you will need to use the best aquarium bacteria starter that you can find.

A bacteria starter kit will make it easier for new fish, plants, and other organisms to adjust to their new environment and hopefully thrive for many years.

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