Best Aquarium Bacteria Supplements For A Healthy Environment

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Adding beneficial bacteria to your aquarium boosts your biological filter’s performance, creating a healthier environment for your fish.

So, what is an aquarium bacteria supplement? Do you really need to use bacteria supplements in your setup? And how do you choose the best aquarium bacteria supplement for your fish tank?

Read this guide to learn how aquarium bacteria supplements work and why using one could be hugely beneficial for the health of your fishy friends.

Quick Comparisons Of The 7 Best Aquarium Bacteria Supplements

IMAGE

Tetra SafeStart Plus Water Treatment in white background

BRAND

Tetra SafeStart Aquarium Bacteria

DETAILS

  • Ideal for starting nitrogen cycle in new tanks
  • Highly effective and quick-acting
Instant Ocean Nitrifying Bacteria Bio-Spira in white background

BRAND

Instant Ocean BIO-Spira

DETAILS

  • Immediately starts nitrogen cycle in saltwater tanks
  • Highly effective and quick-acting
Nutrafin Cycle Biological Filter Supplement in white background

BRAND

Nutrafin Cycle Water Conditioner

DETAILS

  • Immediately starts nitrogen cycle in saltwater tanks
  • Highly effective and quick-acting
API Quick Start Nitrifying Bacteria in white background

BRAND

API Quick Start Water Treatment

DETAILS

  • Excellent in newly planted aquariums
  • Highly effective and quick-acting
Seachem Stability Fish Tank Stabilizer in white background

BRAND

Seachem Stability Fish Tank Stabilizer

DETAILS

  • Excellent for preventing New Tank Syndrome
  • Highly effective
Glosso Factory Dry Format Bacteria in white background

BRAND

Glosso Factory Dry Format Bacteria

DETAILS

  • Lasts for ages
  • Highly effective
Dry Format Bacteria in white background

BRAND

Planted Aquarium Concepts Dry Bacteria Powder

DETAILS

  • Very long-lasting
  • Highly effective

What Is Aquarium Bacteria Supplement And How Does It Work?

Nutrafin Cycle Biological Filter Supplement

Essentially, aquarium bacteria supplements are colonies of beneficial bacteria, which are crucial for a healthy fish tank.

How so?

Why Are Beneficial Bacteria So Important In Your Aquarium?

For the water in your fish tank to be healthy and safe for your fish, you need colonies of beneficial bacteria, specifically Nitrosomonas and Nitrobacter. These bacteria live in your biological filter media, in the substrate, and on surfaces within the tank.

Both those bacteria are critical elements of the nitrogen cycle. The nitrogen cycle is the process through which all types of organic waste in the tank are broken down. As that waste material decomposes, it produces ammonia. Ammonia is highly toxic to fish and causes inflamed gills, shredded fins, loss of appetite, lethargy, swollen eyes, and algae blooms. Eventually, if the ammonia is allowed to build up, your fish will die.

Beneficial bacteria break down ammonia into nitrites, which are still extremely dangerous to your fish. During the next stage of the nitrogen cycle, the nitrites are further broken down into nitrates, which aren’t as toxic. You can then remove nitrates from the water by carrying out partial water changes every week.

When To Add Aquarium Bacteria Supplements

Nutrafin Cycle Biological Filter Supplement

There are several occasions when you should add aquarium bacteria supplements to your tank:

Cycling A New Aquarium

If you’re setting up a brand-new tank, you’ll need to wait at least ten days before you consider adding a few small fish. That’s because the tank needs time for the nitrogen cycle to be completed, rendering the water safe for the fish.

How long the tank takes to cycle depends on how quickly the colonies of beneficial bacteria become established and proliferate enough to cope with processing ammonia. Adding aquarium bacteria supplements helps to accelerate the cycling process and prevents “new tank syndrome.”

New tank syndrome occurs when the water in the tank contains high levels of ammonia and nitrites. NTS is caused by adding fish to the tank too soon before there are enough beneficial bacteria present to cope with the waste that the fish produce. The result is an ammonia spike and often a mass fish kill.

Check The Type Of Bacteria Supplement!

If you’re using a bacteria supplement to cycle a new tank, be aware that some supplements are designed to enable you to skip the cycling process altogether. In contrast, others are only intended to add more bacteria to support what’s already present in the aquarium.

If you use the wrong product, you risk introducing fish to the tank before it’s properly cycled, and your fish might die.

Introducing New Fish To An Existing Tank

Sometimes, adding new fish to an existing setup can overload the biological filter, triggering increased levels of ammonia. Adding a few drops of bacteria supplement can help to prevent that by boosting the size of the bacterial colonies in the tank.

Partial Water Changes

You need to carry out 20% to 30% partial water changes every week to remove nitrates from the tank. 

Part of the process of changing the water involves vacuuming the aquarium substrate to remove accumulations of waste, general detritus, and plant debris. Unfortunately, that also means that you will remove some beneficial bacteria, especially if you clean the glass and decorations.

So, if you add a bacteria supplement to the water, you’ll replace any bacteria you’ve removed, helping to keep the nitrogen cycle ticking over efficiently.

Medicating Your Fish

Unfortunately, some forms of fish medication kill some of the beneficial bacteria present in the tank and the organism that’s causing the disease.

You can mitigate that problem somewhat by placing the fish in a quarantine tank. However, if you need to treat your main aquarium, you can replace some of the beneficial bacteria and boost the numbers in the colonies by adding some bacteria supplement to the water once the treatment has finished.

How Quickly Do Aquarium Bacteria Grow?

Under normal circumstances, it can take from four to six weeks for beneficial bacteria to grow and complete the nitrogen cycle in a new tank.

Adding a filter boost product can halve that time or negate the need to wait before adding fish altogether, depending on the product you use.

Do I really Need To Buy Aquarium Bacteria Supplements For My Aquarium?

No. If you prefer to go the natural route for cycling a new tank, that’s fine. 

That said, I do recommend that you add a bottle of bacteria supplement to your range of fish medications and water treatments, as it’s useful to have. I generally use some to replace beneficial bacteria that I feel I’ve removed during a deep clean and water change.

It’s not thought that aquarium bacteria supplements have any adverse effects on your fish and inverts.

What Are The Different Types Of Aquarium Bacteria Supplements?

Aquarium bacteria supplements come in two main forms:

Liquid Aquarium Bacteria

Tetra SafeStart Plus in white background

Liquid aquarium bacteria are readily available and relatively inexpensive. 

The bacteria are contained in suspension and supplied in a bottle. Simply add the appropriate amount of liquid to your aquarium water, according to the manufacturer’s directions.

Dry Format Bacteria

Dry format bacteria supplements come in powder form. You measure out the required amount of supplement with the scoop provided and add the powder to your tank.

Both forms of bacteria supplement typically contain Nitrosomonas and Nitrobacter strains of bacteria.

How To Choose Aquarium Bacteria Supplements

There are a few considerations to be made when choosing an aquarium bacteria supplement.

Type Of Fish Tank

First of all, you need to choose a bacteria supplement that’s suitable for use in your tank. 

Is your tank marine or freshwater? Is it tropical or coldwater? Those factors are all key when it comes to choosing a supplement that contains suitable bacteria for specific conditions.

What Do You Want The Bacterial Supplement To Do?

As mentioned earlier, you need to choose a supplement that’s formulated for the job you want it to do.

Do you want a filter boost supplement or a tank quick-start product? Make sure you pick the right one so that you get the results you want.

Aquarium Size

There’s no point buying a huge bottle of bacteria if you only have a small tank. Although most bacteria supplements do have a fairly long shelf-life, they do go out of date, and the bacteria will eventually die, rendering the product useless.

Price

As always, we recommend that you buy the best quality product that your budget will stretch to. In general, budget products are usually not as effective as those that are more expensive but made by reputable companies.

Instructions

Look for products that come with detailed instructions for use and dosage. There’s no point guessing and using too much supplement which could harm your fish, or too little that won’t be effective.

Q&A

Here are the answers to some of the most commonly asked questions about aquarium bacteria supplements:

Q: How long do bacteria live?

A: Aquatic bacteria multiply quickly, so the population of bacteria can survive inside the tank for as long as your filter is running.

If the filter fails for any reason, the aquarium bacteria begin to die off within about 30 minutes. All the bacteria in the tank could die within 48 to 72 hours, depending on the density of the colonies.

Q: Does chlorine kill beneficial bacteria?

A: Yes. Chloramines and chlorine will kill the beneficial bacteria in your tank. For that reason, you must always add a dechlorinator to tap water before you introduce it to your aquarium.

Q: How should I store my aquarium bacteria supplement?

A: Store your aquarium bacteria supplement in the container it was supplied in. Put the container in a cool, dry place where the temperature doesn’t fluctuate. Remember, the bacteria are living creatures, and they will die if exposed to excessive heat or cold.

Check the expiry date on the product, and be sure to dispose of the supplement safely once it’s reached that date. There’s no point keeping the supplement once it’s expired, as the bacteria contained might be dead, rendering the product useless.

Q: Does aquarium salt kill beneficial bacteria?

A: No. Unlike many fish medications, aquarium salt is harmless to beneficial bacteria.

Q: Should I use an aquarium bacteria supplement and water conditioner every time I perform a water change?

A: You absolutely must use a water conditioner or dechlorinator product every time you perform a partial water change using tap water. 

The chlorine and ammonia in tap water are lethal to your fish and kill off the beneficial bacteria in the aquarium. That’s why you should never rinse your filter sponges and other filter media in tap water.

Although you don’t need to use a bacteria supplement, water changes and vacuuming the substrate do remove an amount of the beneficial bacteria in the tank. So, adding a bacteria supplement can help to make up the difference and rebalance the population of bacteria, helping to keep conditions in your tank stable.

Top 7 Aquarium Bacteria Supplements Review

Now you understand all about why you should use bacteria supplements in your fish tank, let’s check out some of the best products we’ve found on the market. 

Click the handy in-text links to read full product specs and other users’ reviews. Once you’ve decided on the perfect bacteria supplement for your needs, click to buy!

1. Tetra SafeStart Plus Concentrated Freshwater Aquarium Bacteria

Tetra SafeStart Plus Water Treatment in white background
  • Ideal for starting nitrogen cycle in new tanks
  • Highly effective and quick-acting
  • Inexpensive and economical

Tetra SafeStart Plus Concentrated Freshwater Aquarium Bacteria is one of the most popular bacteria supplements on the market. This product is suitable for use in tropical and coldwater freshwater fish tanks, but you can’t use it in marine setups.

The solution helps to reduce the levels of ammonia and nitrate in new setups and can also be used as part of your regular aquarium maintenance regimen. You can also use the product when adding new fish to an existing tank or when medicating your fishy friends.

The formula is concentrated to provide value for money and contains live beneficial bacteria that accelerate the cycling process in new tanks. The idea is to reduce the time it takes for beneficial bacteria to colonize your tank’s bacterial filter media, reducing the time it takes for the tank to cycle fully.

That said, you do still have to allow up to two weeks for the bacteria to become established before it’s safe to add your fish.

PROS

  • Promotes the fast formation and proliferation of bacteria colonies
  •  Easy to use – just add to the tank water and wait
  • Can also be used for fish-in cycling 

CONS

  • Not suitable for use in marine and reef tanks

2. Instant Ocean BIO-Spira 100mL

Instant Ocean Nitrifying Bacteria Bio-Spira in white background
  • Immediately starts nitrogen cycle in saltwater tanks
  • Highly effective and quick-acting
  • Suitable for fish-in cycling

If you have a marine fish-only or coral reef tank, Instant Ocean BIO-Spira bacteria supplement is your go-to product.

If you’re starting a new marine tank, this product considerably accelerates the development of essential beneficial nitrifying bacteria. The product also works brilliantly at helping to maintain the biofilter in already established coral reef tanks and fish-only aquariums.

You can also use this bacteria supplement after using fish medication that’s compromised your biofilter, following substantial water changes, or, populate new live rock faster. You can also use Instant Ocean’s supplement when you introduce new fish to your setup, helping the biofilter to cope with the increased workload.

The product doesn’t need refrigeration and comes in a robust bottle with a pretty generous shelf-life. This high-quality aquarium bacteria supplement contains a combination of beneficial bacteria, including:

  • Nitrococcus
  • Nitrospira
  • Nitrosomonas
  • Nitrosospira

PROS

  • Promotes the fast formation and proliferation of bacteria colonies and almost instant cycling
  •  Prevents New Tank Syndrome
  • Can also be used for fish-in cycling 

CONS

  • Not suitable for use in freshwater tanks

3. Nutrafin Cycle – Biological A7904 Water Conditioner 500 ml

Nutrafin Cycle Biological Filter Supplement in white background
  • Immediately starts nitrogen cycle in saltwater tanks
  • Highly effective and quick-acting
  • Suitable for fish-in cycling

Nutrafin Cycle Biological A7904 Water Conditioner can be used for freshwater and saltwater tanks, which is excellent news if you have both kinds of setup, as you won’t need to buy two separate products.

Thanks to the high concentration of bacteria contained in the solution, you can expect to reduce cycling time to just over one week, which is considerably shorter than you would get with traditional, natural cycling.

The product is safe for use in tanks containing fish, inverts, and plants, making it ideal for fish-in cycling. You can use this bacteria supplement to top-up and restabilize bacteria levels after a water change, following medication, and when introducing new fish, as well as to kick start the nitrogen cycle in a new tank.

Despite the fact that this product contains live bacteria, it has a relatively long shelf-life, which is handy if you tend not to use much of the product.

PROS

  • Highly concentrated so represents good value for money
  • Reasonably priced
  • Has a long shelf-life in comparison to other similar products

CONS

  • You must remember to shake the bottle vigorously before use or the product isn’t effective.

4. API Quick Start Freshwater & Saltwater Aquarium Water Treatment

API Quick Start Nitrifying Bacteria in white background
  • Excellent in newly planted aquariums
  • Highly effective and quick-acting
  • Suitable for fish-in cycling

API is a well-established manufacturer of fishkeeping products and has a big reputation. Personally, I tend to pick API over other brands simply because I know that their products are reliable, effective, and safe.

API Quick Start is excellent at reducing ammonia levels super-quickly when you introduce new fish to your established freshwater tank. You can also use the supplement after medicating the tank and following large water changes or aquarium deep-cleans.

If you’re using this product to kick off the nitrogen cycle in a new tank, note that this isn’t the quickest-acting starter, taking around two weeks before the water is safe for new fish to be added.

Unlike some bacteria supplements, which pretty much skip the build-up of nitrite during the nitrogen cycle, API Quick Start forces the cycle to follow its correct natural course. So, you’ll notice a nitrite spike immediately following the ammonia spike, and your living plants will quickly take care of the nitrite. Also, it’s still safe to use plant fertilizers while using this bacteria supplement.

PROS

  • Excellent for cycling planted tanks
  • Suitable for freshwater and saltwater aquariums
  • Can be stored safely at room temperature 

CONS

  • Takes around two weeks to fully cycle new tanks

5. Seachem Stability Fish Tank Stabilizer

Seachem Stability Fish Tank Stabilizer in white background
  • Excellent for preventing New Tank Syndrome
  • Highly effective
  • Suitable for fish-in cycling

Seachem Stability is formulated for both marine and freshwater systems and is designed to safely and quickly establish bacterial colonies in the biofilter medium, thus preventing mass fish kills caused by New Tank Syndrome.

This product is created specifically for use in fish tanks, containing a carefully balanced blend of anaerobic, aerobic, and facultative bacteria, which, between them, break down ammonia, nitrite, and nitrate. These bacteria survive in conditions where other types of organisms die off. Also, some species of bacteria can produce hydrogen sulfide pockets in the substrate, but this product is formulated not to do that.

It’s easy to measure out how much you need, simply by using the bottle’s cap. And because the solution is concentrated, you get excellent value for money.

PROS

  • Does not make the aquarium water turn cloudy
  • Suitable for freshwater and saltwater aquariums
  • Can be stored safely at room temperature 

CONS

  • Be sure to use an accurate dose for full effectiveness.

6. Glosso Factory Dry Format Bacteria

Glosso Factory Dry Format Bacteria in white background
  • Lasts for ages
  • Highly effective
  • Contains over 90 species of bacteria

Glosso Factory bacteria supplement is different from most of the other products we looked at because it’s a dry, powder formula. 

The bacteria contained in the product don’t become active until you mix the powder with dechlorinated water. That’s great because it means that the product’s shelf-life is much longer than that of pretty much all the liquid bacteria supplements we’ve reviewed.

Among the 90 strains of bacteria that the product contains are Nitrobacter and Nitrosomonas bacteria that convert ammonia to nitrite and nitrite to nitrate. You can treat 7,100 gallons of water with just one bottle of this stuff, making it superb value for money.

On the downside, this product is not effective if you want to use a fishless tank cycling process simply because the bacteria are quite slow to get going in comparison to liquid bacteria supplements. Also, the powder is only suitable for use in freshwater tanks.

PROS

  • Long-lasting, concentrated formula
  • Long shelf life
  • Bacteria aren’t activated till mixed with water

CONS

  • Unsuitable for use in new tanks as bacteria take some time to become activated

7. Planted Aquarium Concepts Dry Bacteria Powder

Dry Format Bacteria in white background
  • Very long-lasting
  • Highly effective
  • Excellent value for money

Planted Aquarium Concepts Dry Bacteria Powder is another dry product that offers brilliant value to the consumer. Just one ounce of the powder is enough to treat up to 1,925 gallons of water! And one scoop of powder gives you an incredible 1.25 billion bacteria!

The powder has a very long shelf life when compared with liquid supplements, provided you store it somewhere cool, dark, and dry. Thanks to the amazingly high concentration of bacteria contained in the powder, this supplement is very quick to act, taking less time to cycle a small tank. That said, very large tanks can take up to ten weeks to cycle. For that reason, I don’t recommend this product for new tanks.

However, if you want a bacteria supplement that’s excellent value for money, contains the correct strains of bacteria for fish-in cycling, and has a long shelf-life, then this product is an excellent choice for you.

PROS

  • Long-lasting, concentrated formula
  • Long shelf life
  • Excellent value for money 

CONS

  • Not really suitable for cycling brand-new tanks

In Conclusion

I hope you enjoyed our guide to aquarium bacteria supplements and found the information helpful.

Of the products we looked at in this article, our favorite is API Quick Start Freshwater and Saltwater Aquarium Water Treatment. This product is ideal for newly planted tanks and fish-in cycling and highly effective and quick-acting. Also, you can use this product in both freshwater and saltwater tanks. You can also use the supplement to kick start the Nitrogen Cycle in new setups, although you will need to allow around two weeks for the tank to be fish-safe.

Using an aquarium bacteria supplement is extremely helpful when cycling a brand-new tank. But you should also use one following water changes, aquarium deep-cleans, when adding new fish to the tank, and after treating the water with fish medication.

Please feel free to ask any questions you have about bacteria supplements in the comments box below, and remember to share the article if you loved it!

Alison Page has been an avid fish keeper for over 35 years and has owned many different species of freshwater tropical fish including bettas. Currently Alison has two large freshwater tanks. The first tank has two huge fancy goldfish who are almost ten years old and still looking as good as ever. In the other, she has a happy community of tiger barbs, green tiger barbs, corydoras catfish, platys, and mollies.

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