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API TAP WATER CONDITIONER Aquarium Water Conditioner 4-Ounce Bottle, TAP WATER COND. 4 OZ

  • Based on 26,834 reviews
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Availability: In Stock.
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Arrives Tuesday, Aug 25
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Size: Pack of 1


Features

  • Contains one (1) API TAP WATER CONDITIONER Aquarium Water Conditioner 4-Ounce Bottle
  • Neutralizes chlorine, chloramines and other chemicals to make tap water safe for fish
  • Prevents tap water chemicals from causing gill destruction, tissue irritation and fish death
  • Super strength, high concentration formula
  • Use when adding or changing water and when adding new fish to freshwater and saltwater aquariums

Description

Good water quality is the key to a healthy, beautiful aquarium. Tap water contains chemicals, such as chlorine and chloramines, which make water safe for drinking, are highly toxic to fish. High levels of these chemicals destroy fish gill tissue, preventing the uptake of oxygen which can lead to fish death. Even low levels irritate delicate fish tissue. Tap water must be treated before adding fish to make sure fish remain healthy. API TAP WATER CONDITIONER Aquarium Water Conditioner instantly removes chlorine and neutralizes chloramines. It also detoxifies heavy metals in tap water. The formula of API TAP WATER CONDITIONER incredibly concentrated. You only need up to 3 ml to treat 10 gallons of water. It's safe for all aquatic and can be used in both fresh and salt water. Use during aquarium set up, water changes and adding fish. With API Aquarium products, it’s easy to keep a beautiful saltwater, freshwater or reef aquarium. For over 50 years, API has been creating innovative, research-driven solutions that make it easier to care for your fish and aquarium. API Aquarium Treatment Supplies are designed to work in conjunction with each other to provide best results to control algae, promote healthy bacterial growth and help control and cure fish diseases and conditions such as ich and fin rot. They work to provide a safe, hospitable environment for fish such as tropical community fish, cichlids, goldfish and more. With API, you can spend more time admiring your fish, and less time scrubbing your tank. Make sure to use all products as directed in order to ensure the best results.

Brand: API


Liquid Volume: 4 fluid ounces


Item Weight: 4.8 ounces


Item Form: Liquid


Number of Packs: 1


Product Dimensions ‏ : ‎ 1.5 x 1.5 x 6 inches; 4.8 ounces


Manufacturer recommended age ‏ : ‎ 1 month and up


Item model number ‏ : ‎ 52B


Date First Available ‏ : ‎ June 15, 2004


Manufacturer ‏ : ‎ Mars Fishcare


Best Sellers Rank: #640 in Pet Supplies (See Top 100 in Pet Supplies) #2 in Aquarium Water Treatments


#2 in Aquarium Water Treatments:


Customer Reviews: 4.7 4.7 out of 5 stars (26,834)


Brand Name: API


Number of Packs: 1


Unit Count: 1 Count


Manufacturer: Mars Fishcare


UPC: 017163002529


Number of Items: 1


Global Trade Identification Number: 29


Included Components: 1 Bottle 4-Ounce


Item Type Name: Aquarium Water Conditioner


Model Number: 52B


Manufacturer Part Number: 52B


Liquid Volume: 4 fluid ounces


Item Weight: 4.8 ounces


Item Form: Liquid


Pet Type: Fish


Target Species: Fish


Allergen Information: Apple Free


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Tuesday, Aug 25

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

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View our full returns policy here.

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Similar Products

Top Amazon Reviews

    • A Must-Have for Aquatic Health!
Size: 16 ounces
I’ve been using API TAP WATER CONDITIONER for a few weeks now, and I’m extremely impressed with its effectiveness in keeping my aquarium water clean and safe for my fish. Here’s why I’m giving it a 5-star review: 1. Perfect for New Aquariums and Water Changes: I’ve recently set up a new tank, and this conditioner has been a lifesaver. It quickly removes harmful chlorine, chloramine, and heavy metals from tap water, which could be toxic to fish. It ensures the water is safe to use without waiting for the water to sit for days. 2. Safe and Effective for All Fish Species: Whether I’m adding new fish to my tank or doing a routine water change, I feel confident using this product. It’s safe for all types of freshwater fish, including my delicate species. I haven’t noticed any signs of stress in my fish after water changes, which speaks volumes about the quality of this conditioner. 3. Easy to Use: The API TAP WATER CONDITIONER is super easy to use. I simply add the recommended amount per gallon of water, and it instantly works its magic. No hassle, no mess—just pour and go! 4. Great Value for Money: Considering the price and the amount of product you get (16 ounces), this conditioner is a great value. It lasts for a long time since you only need a small amount with each water change, making it an affordable option for any aquarium owner. 5. Fast Acting: The conditioner works fast! I can fill the tank with treated water and immediately begin acclimating new fish. I’ve had no issues with cloudy or unsafe water when using this conditioner, and it’s consistently kept the water quality at its best. 6. Trusted Brand: API is a well-respected brand in the aquarium industry, and it’s a name I trust when it comes to my fish’s health. Their products are always reliable and effective. Final Thoughts: If you’re an aquarium owner, whether you’re new to fishkeeping or a seasoned pro, I highly recommend the API TAP WATER CONDITIONER. It’s safe, affordable, and does exactly what it promises—ensures clean, safe water for your fish and keeps them happy and healthy. 💯 Five stars – a must-have for any aquarium enthusiast! ... show more
Reviewed in the United States on February 17, 2025 by Tino Bruno
    • Great, especially for larger volumes.
Size: 16 ounces
Review Image by I am K8
I have bonsai and small plants and needed a water conditioner to remove chloramines, which are used in an abundance of tap water instead of chlorine. I only need to clear 1 quart to 1 gallon (4 q), but this stuff is made for large amounts. For chloramines, you add 5ml per *30* gallons. The top measures 5ml. Thus I only add a literal *drop* from a 1ml syrine into my 1qt buckets. For me, it's a great value - it'll last forever, lol. For aquariums, obviously less time, but the price per oz of this was better than the other conditioners I saw, sooo it seems like a good value for all. ... show more
Reviewed in the United States on July 11, 2026 by I am K8
    • The best value for tap water treament
Size: 128 ounces
I love all of the API products, especially their easy to use test kits. This product is great as well. Regardless of which size you buy of their tap water conditioner, it is the best value of reputable brands that will treat all tap water for your pond or tank. It only requires 3 drops per gallon you add to your tank. It removes chlorine, neutralizes chloramines, and helps detoxify any heavy metals in your tap water. Some more expensive products will claim to also include things to help your fish maintain their protective slime coating (and cure male pattern baldness and perhaps ED). If your fish are healthy, and your tank's water parameters are maintained well through weekly water changes and good filtration, those other ingredients are useless. (The "Special Sauce" is just ketchup, mayonnaise, and relish.) If your fish have sores or other health problems, then find the cause, fix it, and treat them with something besides a tap water conditioner if needed. Like every other tap water treatment API's instructions first tell you an amount of the product required to remove chlorine, and then in smaller print below say to use 2 to 3 times as much to also neutralize the more toxic chloramines that may be added during the purification of your water. I don't know why the companies that make these products won't be honest and say up front to use the higher amount, and then in small print say you can skimp and use less if you want to save money and risk the health of your fish. If you have confirmed with your local water authority that they do not use chloramines during their treatment or your water, then it only requires a single drop per gallon to remove chlorine. I did not bother to call my county water authority, since I had no way to confirm that the person who answered the phone would know chlorine, chloramine, nor chloroform for that matter. from their own colon or a hole in the ground. Even if you personally spoke to someone that could tell you for dead certain that chloramines are not being used, they are not going to text you if that changes in the future. Unless you are the person in charge of that step of water treatment for your area, the only way to know for certain if your water was safe for your fish with only a single drop per gallon, is if you use one drop, then test that water for any detectable ammonia that is the treated water. The chloramines contain a small amount of ammonia. Then you would know it was safe to add to your tank without causing them irritation and inflammation of their gill tissue. It is much safer to simply to add 3 drops per gallon. More doesn't hurt anything, but it's just wasted. To refill my tanks, I keep a pair of 5 gallon plastic bottles that were used for filtered / spring water. After I fill my tanks, I add the tap water treatment to the jug, refill it, and let it sit until I need it. This allows the conditioner time for its anti-heavy metal ingredients to work fully. It also lets the water come to room temperature, since 5 gallons of icy cold tap water in winter can cause the temp to drop in a 55 gallon tank. Perhaps more importantly, the water lines in many places are old and require frequent repairs or expansion. When repairs are made to water mains, they sometimes add extra chlorine disinfectant at the repair site to insure that any bacteria that might have gotten introduced to the main are killed and cannot grow and contaminate our drinking water. While I cannot normally detect a smell of chlorine in my tap water, I occasionally notice that it smells a bit more like a swimming pool than tap water. If more chlorine than normal is in the tap water, then more neutralizer would be needed. Most Chlorine will gas off on its own if the tap water is left uncovered for 24 hours, but Chloramine will not. When they disinfect a repair site, they are normally only using chlorine. By leaving the water I will add to my tank sitting for at least a day, then I am positive that it is always safe to add to my tank. I have had people ask me before if they can add the conditioner to the tank and then use a water hose to refill their tank. I don't normally recommend this because many of our fish are conditioned to come to the part of the tank where we are standing and adding water, because they think food will soon be added as well. If you add the conditioner to the tanks water rather than to the tap water first, then the tap water from a hose will take a short while to react with the treatment additive. Temporary short spikes of chlorine won't kill your fish, but cumulatively over time, it's not good for them either. Also unless you have a hose that is certified safe for drinking from, it can leach harmful chemicals into the water you're adding to the tank. If you are using a normal garden hose to refill your tank after water changes, at the minimum you should run water through it first for a few minutes to make sure that any that has been standing in the hose is washed out. ... show more
Reviewed in the United States on March 24, 2017 by gtippitt
    • Excellent value. Have been using for years. Would never buy anthing but this.
Size: 128 ounces
I swear by this stuff. It's perfect for water changes. I use it in all my aquariums and in my pond. I never mix water first. I just do it in the tank. I do add water slowly though. It has no smell or color. It works very fast. It is highly effective. I add one cap full for every 30 gallons of water in my tank and it always works. It says add such and such for every gallon that you add, but I do the math by the water volume of my tank since I am adding tap water directly to my tank. A couple of drops is all you need for a gallon if you are only topping it off. I do about 70% water changes biweekly using this stuff. If you are having dead fish most likely the issue is because of temp, adding it too fast, or you just need to add more. I have even added way more than it needed by accident. It had literally no effect on my fish or plants at all. Very hard to overdose your tank unless you dump in the whole bottle. I do wear gloves when using this product. Can't be too careful. And eye protection too. ... show more
Reviewed in the United States on November 4, 2025 by MK
    • Good
Size: 16 ounces
Review Image by Julianna Teeman
Review Image by Julianna Teeman
Review Image by Julianna Teeman
Suchhhh a good price for the bottle size. More worth it than buying in stores. Only issue I had was the bottle can in a box without and cushioning. Scared it could’ve broke while in shipment.
Reviewed in the United States on March 26, 2026 by Julianna Teeman
    • Worth your money
Size: 16 ounces
This is very good stuff and I just bought another one
Reviewed in the United States on July 30, 2026 by Renee M.
    • Great product.
Size: 16 ounces
Great product. I use it in my aquatic turtle’s aquarium. He is 21 years old so I think this speaks well of this product that I’ve used almost his entire life.
Reviewed in the United States on August 16, 2026 by Cheryl
    • Great Water Conditioner
Size: 16 ounces
This water conditioner works exactly as expected. It quickly makes tap water safe for fish by removing chlorine and chloramines, and it’s easy to dose. A reliable product that gives peace of mind during water changes.
Reviewed in the United States on July 18, 2026 by Tani Acosta

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