Clean and healthy tank water is essential for your fish to be healthy and happy. Therefore, you should perform weekly tank maintenance and cleaning to keep ammonia, nitrite, and nitrate levels to a minimum.
That process involves changing some of the water, but tap water contains chemicals, minerals, and heavy metals that keep the water safe for us to drink, but make it deadly to fish. Fortunately, you can solve that problem by using a tap water conditioner.
But how long does the water conditioner take to work? And what is the best water conditioner for aquariums? In this guide, we tell you everything you need to know about tap water conditioning products, including detailed water conditioner reviews and our personal recommendations.
Quick Comparisons of the 6 Best Aquarium Water Conditioners
| IMAGE | BRAND | DETAILS | |
|---|---|---|---|
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API Tap Water Conditioner |
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See product |
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Tetra AquaSafe Plus Freshwater and Marine Aquarium Water Conditioner |
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See product |
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Seachem Prime |
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See product |
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aqueon tap water conditioner |
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See product |
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Fluval water conditioner for aquariums |
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See product |
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Tetra Easy Balance Plus weekly water conditioner for freshwater aquariums |
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See product |
What is an aquarium water conditioner?
An aquarium water conditioner is a liquid chemical added to the tank to neutralize chlorine, chloramine, and other harmful substances in tap water. Unfortunately, even though your local water company adds these chemicals to the power grid to make the water safe to drink, the chloramine and chlorine can be fatal to fish and plants.
Chlorine and chloramine
Traditionally, chlorine has been added to tap water for disinfection purposes and to kill bacteria. Years ago, you could make tap water safe for your fish tank by letting the water sit in a bucket for 24 hours, stirring it occasionally. Chlorine is a relatively unstable chemical that evaporates into the air after a day or so, meaning your bucket of tap water would be safe for your fish.
However, these days water companies often use chloramine instead of chlorine because it is more stable. Chloramine belongs to a group of chemicals that contain chlorine and ammonia, which is lethal to fish. Unfortunately, chloramine does not evaporate in the same way that chlorine does, so the “rest and stir” tank water purification method is no longer effective.
How do aquarium water conditioners work?
Tap water conditioners neutralize the chlorine contained in the water by forming ionic bonds that render chlorine harmless. Simply explained in layman’s terms, the water conditioner acts like a magnet, drawing chlorine molecules away from the fish’s sensitive gills and making the water safe for use in the fish tank.
However, if your water contains chloramine in addition to chlorine, you’ll need to use a conditioner that can split the ammonia/chlorine bond and treat each one individually. To complicate matters, many water companies routinely switch between using chlorine and chloramine. Therefore, it is safer to use a tap water conditioner that takes care of both.
Types of tap water conditioners
There are three main types of tap water conditioners that you will see for sale at your local fish store:
Dechlorinators
Dechlorinators contain small amounts of sodium thiosulfate, which effectively removes chlorine. However, these products do not work with chloramine.
Chloramine Neutralizers
Chloramine neutralizers are extremely useful products that are formulated to combat chlorine, ammonia, and sometimes heavy metals as well.
These products work by breaking down chloramine and neutralizing ammonia in one of two ways:
- By binding to ammonia molecules, it renders them harmless to fish.
- By converting ammonia to ammonium, which is also harmless to fish.
Please note that if your ammonia test kit is not specifically intended to test water for the presence of ammonia (NH3), it may show that the water contains ammonia (NH4), which is harmless to fish. So always check that you have a test kit that only tests for NH3.
Complete water conditioners
Complete water conditioning products are designed to treat chlorine, ammonia, heavy metals, and even copper, which is helpful if your home has old copper or lead pipes. Complete water conditioners can also function as pH buffers, contain chemicals that offer protection for your fish’s slime coats, and more.
Check the product label to see exactly what actions the conditioner offers, as that varies by brand.
Can a water conditioner be used in marine aquariums?
Water conditioners should not be used in a salt water tank unless in an emergency. That’s because water conditioners don’t remove chloramine from water, they neutralize it. So even though the water is safe for your fish, it still contains a valuable food source for algae and cyanobacteria.
A better water treatment option for a saltwater tank is deionization or reverse osmosis (DI/RO), which does not have the same problem. If you decide to use a water conditioner and you have a protein skimmer, choose a product that won’t cause the protein skimmer to foam.
What about the plants?
Chlorine, chloramine, and heavy metals don’t just harm fish; they can also kill your plants. So if you have live plants in your tank, using a water conditioner will help keep them safe and healthy as well.
home water conditioners
In addition to specific aquarium water conditioners, there are some products and devices that you can use to treat the water that reaches your home through the network. In some areas, the water contains many minerals, such as calcium. The high levels of minerals make the water «hard.» Hard water can taste unpleasant, and the hard mineral deposits that remain can cause problems with appliances and plumbing systems.
Water that contains a lot of calcium can also cause problems in your aquarium. Hard, white mineral deposits can coat light units, filtration system piping, and the underside of the tank hood.
However, there are some improvements to your home’s plumbing system that can help combat hard water problems. Keep in mind that these water conditioning devices do not make tap water safe for use in your fish tank, and you will still need to use an aquarium water conditioner.
magnetic water conditioner
Magnetic water conditioners can be added to your home’s plumbing system to help remove limescale. These devices direct the water through a strong and uniform magnetic field by placing two powerful neodymium magnets on each side of the inlet pipe.
Magnetic water treatment does not extract calcium from the water, which means that on paper, the water is just as hard as it was before it passed through the magnets. However, the magnets are claimed to change the structure of the calcium deposits that form, making the minerals less likely to stick to pipes and other surfaces. Therefore, you may not experience the problems that hard limescale buildup can cause if you install a magnetic water softener.
tank water conditioners
Tank water conditioners are units that process the water that enters your home, remove minerals that harden the water, and use sodium and potassium to condition the water. Water conditioning devices come in different sizes.
metered water conditioner
Metered water conditioners are the most economical form of tank water conditioners for the home. Metered units only regenerate water when a preset volume of softened water has been used, regardless of how long it takes. This system prevents over or under regeneration of the water softener when water demand varies.
The volume of treated water is calculated based on the amount of minerals in your water supply, the number of people living in your household, and the capacity of the water conditioning unit you have installed.
digital water conditioners
Digital water conditioning units are a popular choice with households as these devices are generally more efficient than the more traditional analog version. Digital conditioning units use less potassium and salt, and some include additional features like chlorine removal and heavy metal filters, which is good news for fish farmers. Plus, these devices are cheaper to operate and require very little maintenance than their older-style counterparts, saving you money in the long run.
Why do you need a water conditioner?
Tap water is not safe for fish because it contains chlorine and chloramine that can damage sensitive gill tissue in fish. You should use a suitable water conditioning product, such as the ones we recommend in the product review section later in this guide, to make the water safe for your fish before adding it to your tank.
You can also make your tap water more palatable to drink and less harmful to your home’s plumbing by installing a home water softening unit, as described earlier in this article.
Benefits of water conditioners
Using water conditioners has many benefits, both for your family and for your fish!
- Water conditioners are easy to use and relatively inexpensive to install.
- Home water conditioners can help reduce scale and blockages in household pipes and appliances, saving you money on costly repairs.
- Water conditioners make aquarium water safe for your freshwater fish and plants by removing ammonia and chloramine without affecting the pH level of the water.
- Some aquarium water conditioners help maintain the fish’s protective layer of slime.
How often to use an aquarium water conditioner
As a general rule of thumb, you should use an aquarium water conditioner whenever you do a partial water change on a set setting. The idea is to neutralize the ammonia and chloramine in the tap water you add to your tank. Therefore, whenever you need to add fresh tap water to your aquarium, you will need to first treat the water with a water conditioner.
When to add water conditioner
Tap water should always be conditioned when you install a new tank and during every partial water change thereafter.Add the water conditioner to a bucket of clean tap water, according to the manufacturer’s dosage instructions, and then add the treated water to your fish tank.
I prefer to add the prescribed dose of treatment to the bucket while the water is running so the product mixes with the water. When the bucket is full, the water conditioner is activated and water can be added to the tank.
new aquariums
When setting up a new tank and using the fishless cycle method, you should use a basic dechlorinator, rather than a full tap water conditioner. Although you want to neutralize the chlorine and chloramine, you don’t want to remove the ammonia at this stage. This is because your beneficial bacteria need ammonia to start the nitrogen cycle.
partial water changes
After the initial tank setup, and any time you do a partial water change in the future, you should treat the tap water you add to the tank with a complete tap water conditioner. If you don’t, you risk killing the beneficial bacteria in your filtration unit and harming your fish.
How much water conditioner?
There is no general rule for dosage levels of water conditioners. The amount to use depends on the brand and nature of the product.
Always follow the manufacturer’s instructions for dosing and use the special pipette or measuring cup provided with the product to accurately measure the conditioner.
How long does a water conditioner take to work?
Water conditioners are generally very fast acting. Most of these products neutralize chlorine and chloramine in a bucket of tap water in five minutes or less. Again, check the manufacturer’s guidelines for approximate time frames.
What to look for when buying an aquarium water conditioner
There are a few things to keep in mind when choosing an aquarium water conditioner:
- a formula that includes protection against chloramine, chlorine, ammonia, nitrites and heavy metals
- a product that is suitable for use in freshwater and saltwater tanks (if applicable)
- a conditioner that increases slime production
- a formula that adds electrolytes to the water to encourage good growth and healthy fish
You should also read the product label carefully to see what chemicals the formula works with. To provide comprehensive water care for your fish, you may need to use additional treatment.
Top 6 Aquarium Water Conditioner Reviews
In this part of our complete guide, we have selected six of the best aquarium water conditioners on the market at the time of writing. Each product is provided by a reputable manufacturer and is safe and effective for use in your aquarium.
1. API Tap Water Conditioner
- 16 fluid ounces
- One drop per gallon
- Neutralizes chlorine, chloramine, detoxifies heavy metals
Check the price
API is a highly respected manufacturer of aquarium products, including a wide range of water treatments.
This particular offering from API is a basic tap water conditioner, which works well for neutralizing chlorine and detoxifying heavy metals. The formula is also concentrated so you don’t need to use a large amount each time you add water to your tank, helping to keep costs down. As you would expect from API, a clear dosage chart and measuring cap are included with the product.
However, the conditioner does not contain anything that detoxifies or removes ammonia. Therefore, if the tap water contains chloramine, the ammonia will remain after the chlorine has been removed.
| PROS | CONS |
|---|---|
| Excellent value for money Neutralizes chlorine Detoxifies heavy metals |
No slime booster Does not attack chloramines |
2. Tetra AquaSafe Plus Freshwater and Marine Aquarium Water Conditioner
- 16.9 fluid ounces
- 5ml per 10 gallons
- Neutralizes chlorine, chloramine, detoxifies heavy metals
Check the price
Tetra manufactures a wide range of aquarium water treatments, fish feeds and hobby-related equipment. Tetra’s Aquasafe Plus product can be used in freshwater and marine tanks, although they recommend that you remove your protein skimmer before adding the product to the water.
The conditioner combats chlorine, chloramines and heavy metals, and also contains algae extract to stimulate bacterial growth. A slime coating enhancer is added to the product to protect fish from parasite attack and accidental injury. As an added benefit, the product contains essential minerals and vitamins to help fish thrive.
The product is super easy to use. You can squeeze the bottle to dispense individual drops or use the cap to measure out the required dose.
| PROS | CONS |
|---|---|
| Excellent value for money Neutralizes chlorine and chloramine. Contains vitamins, minerals and slime layer stimulators. |
Expensive compared to other similar products |
3. Seachem Prime
- 3.4 fluid ounces
- 1 ml per 10 gallons
- Neutralizes chlorine, chloramine, detoxifies heavy metals
Check the price
Seachem Prime is the company’s flagship product, and the conditioner’s super-concentrated formula offers excellent value for money, as you don’t need to use as much as you do with many other water conditioners.
Prime neutralizes chlorine and chloramine, converts ammonia to a non-toxic form, and detoxifies nitrites and nitrates, lightening the load on your biofilter. The product does not affect the pH of the water, although it makes heavy metals safe for fish and plants. You can use the conditioner in a marine aquarium without fear of it over-activating your protein skimmer. As an added benefit, the conditioner stimulates the natural regeneration of the fish’s slime coat.
It is easy to measure the correct dose using the calibrated cap. Each thread on the cap equals about 1 ml, so you can easily calculate how much you need at 5 ml (or one cap) per 50 gallons of water.
| PROS | CONS |
|---|---|
| Excellent value for money Neutralizes chlorine and chloramine. Contains a slime layer booster |
Instructions can be difficult to memorize |
4. aqueon tap water conditioner
- 16 fluid ounces
- 5ml per 10 gallons
- Neutralizes chlorine, chloramine, detoxifies heavy metals
Check the price
aqueon is a very popular brand of tap water conditioner that instantly neutralizes chlorine and chloramines, as well as detoxifying ammonia, heavy metals and fish waste. As an added benefit, aqueon tap water conditioner helps restore fish’s natural slime layer that can be lost when fish are shipped or fished. This water conditioner also helps reduce fish stress, making it a great choice for new setups.
The correct dosage of water conditioner is easy to measure using the calibrated dosage cap.
This is one of the cheapest water conditioning products we’ve seen, but it does more or less what all the other brands do at a slightly cheaper price.
| PROS | CONS |
|---|---|
| Excellent value for money Contains a slime layer booster Reduces fish stress |
She tends to use more of this conditioner than other products, which negates the cost effectiveness of the product a bit. |
5. Fluval water conditioner for aquariums
- 15.9 fluid ounces
- 5ml per 10 gallons
- Neutralizes chlorine, chloramine, detoxifies heavy metals
Check the price
Fluval Aquarium Water Conditioner is a complete and highly effective product that neutralizes chlorine and chloramines in tap water, as well as removing harmful heavy metals. In addition, the product contains a special proprietary stress-relieving formula that protects fish fins and scales, preventing inflammation that can result from bumps and scrapes.
The water conditioner also contains pure herbal extracts that can reduce stress on fish during handling, transport and acclimatization to a new aquarium. The product is suitable for use in fresh and salt water tanks.
We believe that fluval’s product offers the hobbyist excellent value for money due to its all-in-one formula.
| PROS | CONS |
|---|---|
| Excellent value for money Contains herbal extracts to reduce stress. Suitable for fresh and salt water tanks. |
Not suitable for tanks with snails . Contains aloe which can leave residue in the tank. |
6. Tetra Easy Balance Plus Weekly Freshwater Aquarium Water Conditioner
- 8.45 fluid ounces
- 5ml per 5 gallons
- Reduces nitrates and phosphates, stabilizes pH
Check the price
As a tank matures, the chemistry of the water changes. That’s where Tetra’s EasyBalance Plus Water Conditioner comes in, preventing various harmful conditions that can affect your fish as a result of those environmental changes.
The product can reduce the pH and alkalinity of the water, helping to maintain optimal and stable levels. Additionally, this conditioner reduces nitrates and phosphates in the water that are generated by fish waste. Another benefit you get with this product is the minerals, vitamins, and electrolytes it contains, keeping your fish active, healthy, and thriving.
Please note that this product is not a conditioner for tap water. As such, it does not neutralize chlorine or chloramines. Nor can the product be used in aquariums that have little oxygenation of the water. If you want to use this conditioner, you should add an air stone to your setup if needed.
| PROS | CONS |
|---|---|
| Reduces phosphates and nitrates Contains electrolytes, vitamins and minerals for the health of the fish. Can lower pH and alkalinity in mature tanks. |
Does not neutralize chlorine or chloramines Unsuitable for use in low oxygen tanks |
In conclusion
Before you add tap water to your fish tank, you should take steps to neutralize harmful chlorine, chloramine, and heavy metals. We hope you have found our complete guide to aquarium water conditioners helpful and informative. Now, armed with that knowledge and the right aquarium water conditioning product, you can be sure that your fish can enjoy safe and healthy water.
Our favorite and most recommended water conditioner that we review for you is Seachem Prime. This water conditioner is highly concentrated, which means you don’t need to use as much of this product as you do with most other conditioners, saving you a lot of money over time.
Prime neutralizes chloramine and chlorine, detoxifies nitrate and nitrite, makes heavy metals safe, and converts dangerous ammonia into a harmless, non-toxic form. The pH of the water is not affected by the product and you can use it in both freshwater and marine tanks. As an added benefit, the product’s formula encourages the natural regeneration of your fish’s protective slime layer.
