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Seachem

Seachem Prime 250ml

  • Based on 16,815 reviews
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Availability: 19 left in stock
Fulfilled by Kens Fish
Arrives Feb 28 – Mar 4
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Size: 250 mL


Style: Conditioner


Features

  • POWERFUL TREATMENT: Seachem Prime is a complete and concentrated conditioner for both freshwater and saltwater fish tanks, working hard to remove chlorine and chloramine.
  • REMOVER: Seachem Prime immediately and permanently removes chlorine and chloramine, successfully allowing the bio filter to remove ammonia, nitrite, and nitrate while they are detoxified for 48 hours.
  • DETOXIFIER: Seachem Prime effectively detoxifies ammonia, nitrite, and heavy metals found in the tap water at typical concentration levels, providing a ideal environment for your betta, tetra, or other fish.
  • USE: Use 1 capful (5 mL) of Seachem Prime for each 200 L (50 US gallons) of new or replacement water. For best results, add Seachem Prime to new water first. For exceptionally high chloramine concentrations, a double dose may be used safely. For smaller volumes, use 2 drops per gallon.
  • SAFETY: In case of an emergency, the 5x dose of Seachem Prime may be used for both ammonia and nitrite. Use a 12 dose if the water temperature is > 30C (86F) and chlorine or ammonia levels are low.

Description

Seachem Prime is a complete and concentrated conditioner for both freshwater and saltwater fish tanks, working hard to remove chlorine and chloramine. For over three decades, Seachem has been a company rooted in sound science. Our experience in the hobby and an educated staff of chemists and biologists are part of the package when you purchase Seachem products. Seachem remains as one of the few surviving independent and privately owned pet care companies. Seachem is owned and operated by hobbyists. All of our employees are hobbyists who maintain aquariums at home and at the office. Seachem itself was started because one such passionate hobbyist - Dr. Leo G. Morin (Founder) - recognized that the available solutions to aquarists problem wanting. This resulted in Seachem’s very first product: Cupraplex (today known as Cupramine). Over thirty years later Seachem is still approaching old problems in a new way. Seachem’s philosophy is that the knowledgeable hobbyist makes the best customer. This is reflected in solid and reliable customer education and support as well as products proven in science and performance. While Seachem has grown rapidly into a national and international firm, it retains the culture of a small company and is readily available to its customers.

Brand: Seachem


Liquid Volume: 250 Milliliters


Item Weight: 10.2 Ounces


Item Form: Liquid


Manufacturer: Seachem Laboratories, Inc.


Is Discontinued By Manufacturer ‏ : ‎ No


Product Dimensions ‏ : ‎ 6.1 x 1.8 x 1.8 inches; 10.2 ounces


Manufacturer recommended age ‏ : ‎ 1 month and up


Item model number ‏ : ‎ 67104360


Department ‏ : ‎ Unisex-Adult


Date First Available ‏ : ‎ October 2, 2001


Manufacturer ‏ : ‎ Seachem Laboratories, Inc.


Best Sellers Rank: #509 in Pet Supplies (See Top 100 in Pet Supplies) #1 in Aquarium Water Treatments


#1 in Aquarium Water Treatments:


Item Weight: 10.2 ounces


Department: Unisex-Adult


Manufacturer: Seachem Laboratories, Inc.


Item model number: 67104360


Date First Available: October 2, 2001


Item Package Dimensions L x W x H: 6.61 x 1.93 x 1.89 inches


Item Dimensions LxWxH: 6.1 x 1.8 x 1.8 inches


Item Weight: 10.2 Ounces


Brand Name: Seachem


Target Audience Keyword: fish


Directions: Use 1 capful (5 mL) for each 200 L (50 US gallons) of new water. For smaller volumes, please note each cap thread is approximately 1 mL. May be added to aquarium directly, but better if added to new water first. If adding directly to aquarium, base dose on aquarium volume. Sulfur odor is normal. For exceptionally high concentrations, a chloramine double dose may be used safely. To detoxify nitrite in an emergency, up to 5 times normal dose may be used. If temperature is > 30 °C (86 °F) and chlorine or ammonia levels are low, use a half dose.


Country of Origin: United States


Model Name: 075223


Color: clear, could contain black flakes


Size: 250 mL


Material: Plastic


Age Range Description: all ages


Number of Items: 1


Style: Conditioner


Included Components: Seachem Prime 250ml


Specific Uses for Product: Active


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Feb 28 – Mar 4

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

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews

    • 20+ Years of Flawless Performance!
Size: 1000 mL Style: Conditioner
The media could not be loaded. As someone who's been deeply involved in the aquarium hobby for over two decades, I can confidently say that Seachem Prime is, without a doubt, the single most essential product in my fish room. I was introduced to Prime when I first started out, and it quickly became the cornerstone of my water care routine. Twenty-plus years later, it remains the only water conditioner I trust and use in all my tanks. Prime does exactly what it promises, and it does it exceptionally well. It instantly neutralizes chlorine, chloramine, and ammonia, making tap water safe for your aquatic inhabitants. Beyond that, it detoxifies nitrite and nitrate, which is a huge bonus, especially during cycling or in emergency situations. The fact that it does all of this in a concentrated formula means a little goes a very long way, making the 1L bottle incredibly economical and long-lasting. What truly sets Prime apart, for me, is its reliability and the peace of mind it provides. I've never had a single issue with water parameters or fish health that could be attributed to Prime. It's truly a "set it and forget it" product that allows me to focus on the joy of the hobby rather than worrying about water quality. If you're new to the hobby, do yourself a favor and start with Prime. If you're a seasoned aquarist looking for the best, you already know what I'm talking about. I exclusively use Seachem products in my tanks because their quality and effectiveness are unmatched, and Prime is the shining star of their lineup. This isn't just a water conditioner; it's an investment in the health and longevity of your aquatic ecosystem. Five stars, hands down! ... show more
Reviewed in the United States on May 29, 2025 by Alicia
    • Great product
Size: 500 mL Style: Conditioner
From Cichlids to Fancy Goldfish I've been keeping fish for 30+ years.Just about every major manufacture and boutique specialty company has a water conditioning and treatment product.I can't say I've tried them all, but close too it. Some products have at the least, minimal effectiveness while others can be potentially dangerous. An example would be Stress Coat which has binding sugar strands in the Aloe. This isn't a problem unless one of your fish has a small scratch or wound.The sugar feeds the bacteria which can lead to major infection and dire consequences.I've been using Amquel for years and it's a fine conditioner, excellent at removing chlorine, and Chloramines, but like all these products - they come with limitations. Well, with one exception and that's Prime by Seachem. A few months ago, I decided to give it a try, and haven't looked back since. Prime doesn't just remove the chlorine and Chloramine it does much more: * Detoxifies any and all heavy metals in your tap water (you can call your water company directly for a list of them and PPM) * Neutralizes Ammonia * Neutralizes Nitrite * Neutralizes high Nitrate to non toxic levels * Removes toxic gases * Will not foam or change PH * Helps regenerate natural slime coat Since using Prime, I've seen a dramatic improvement in all of my fish. In 2010 one of tanks was hit with the dreaded and rare Toxic Tank Syndrome - within 48 hours I had lost nine gorgeous fish - except for one survivor, a single Broad Tail Nymph.Since that ordeal, "Roxy" became a bottom dweller spending most of her time laying in a corner. Treatments were conservative, but nothing worked. After my first 50% water change using Prime her behavior began to improve. Now she swims among her tank mates, her color is better, gill movement stabilized and her appetite ferocious. In fact I see improvements in all my fish and in every tank.There simply isn't anything like it, Prime is hands down one of the best things you can do for your fish. In addition to the outstanding, patented formula of Prime - it couldn't be more economical to use. A single 500 ml bottle treats up to a whopping 5,000 gallons of water. A tiny bit goes a long, long way.It should also be noted that in times of emergency the dose can be increased five times, Prime is harmless to fish.It's the only product of it's kind, and towers above any other water treatment on the market - period. If your an aquarium hobbyist be it novice or advanced - I would urge you to add a bottle of Prime to your arsenal of fish care products. Your finned friends will thank you for it. ... show more
Reviewed in the United States on April 6, 2025 by James Williams
    • Works wonders
Size: 500 mL Style: Conditioner
Review Image by Cory Cory
Doing an emergency fish in cycle for my tank and this stuff is amazing. Can get me through the trials of being a new fish owner and keep him safe till healthy bacteria is established in my tank. Performing Emergency fish-in cycle with Seachem Prime Step 1: Set up your aquarium It’s time to set up your aquarium. And, that includes all the equipment – heaters, filters, air pumps… Get it in there! Don’t forget to rinse it with fresh water first! The beneficial bacteria need a surface to cling to, namely your substrate and filter media. So by setting everything up, you give your bacteria as many surfaces as possible to cling to. Add water to the tank, and don’t forget to dechlorinate it with your water conditioner first. Finally, you want to keep all electrical equipment, such as heaters, filters and bubblers, switched on throughout the entire cycling process. Not only will this keep your fish as comfortable as possible, but it will also make your tank cycle faster. Want to cycle your tank as quickly as possible? Check out FishLab’s tips for speeding up the cycling process. Step 2: Adding your fish Before you add your fish, you want to acclimate them first. This will give them the best chance of survival. You want to feed your fish throughout the cycling process… You don’t want them to starve! When feeding your fish, however, it’s important that you don’t feed them too much. The more you feed them, the more they are going to poop. And the more they poop, the faster your ammonia levels are going to rise. Also, remove any uneaten food from the tank, a good aquarium net will make this easy. Any uneaten food left behind will break down into ammonia, causing the levels to rise. If a fish dies during the cycle, remove it from the aquarium ASAP. Its decaying body will also give off ammonia. Don’t panic if one of your fish dies. It doesn’t necessarily mean that all your fish will – this one might have been extra sensitive. Step 3: Test, test, test, and test again Now, use your ammonia test kit every 24 hours. What you are looking for is any sign of ammonia. Trust me. It won’t be long before it appears. Once your test kit returns positive for ammonia, it’s time to move to the next step. Step 4: Dealing with ammonia Once you detect ammonia, it’s time to start dosing with Seachem Prime. Follow the instructions on the bottle to determine what a single dose would be for your tank – the larger the aquarium, the more Prime you will need. Fortunately, a little goes a long way, and many of you will find that a single bottle of Prime will get you through an entire cycle. For this method, Seachem Prime is the most important ingredient. You see, a dose of Prime will bind ammonia, nitrite and nitrate for 24 to 48 hours, making them harmless to your fish. Picture Seachem Prime locking up ammonia, nitrite and nitrate in a jail cell for up to 48 hours. While in the cell, these nasties cannot harm your fish. However, once their time is up, and they are released, they will once again attack your fish. It is for this reason that you need to dose regularly with Seachem Prime, to keep these nasties locked up. A single dose of Prime will treat up to 1 part per million (ppm) of ammonia. Prime can be dosed up to 5 times safely. So, 2 ppm of ammonia can be treated with two doses of Prime, 3 ppm can be treated with three doses, and so on. Anything less than 1 ppm should be treated with a single dose. Between 1 ppm and 2 ppm, two doses. You get the idea. Oh, and it goes without saying that it’s better to overdose than underdose. *Once your test kit reads 2 ppm of ammonia, you should perform a 50% water change. This should cut your ammonia levels roughly in half. Repeat this process until you notice that your ammonia levels are not rising as quickly as before. Typically, this will take a week or two. When this happens, you are ready to move to the next step. Bookmark this page so that you can easily find it when you are ready for the next step! Step 5: Nitrites start to appear Next, you need to test for nitrites. If none are present, keep repeating the previous step and testing for nitrites daily until you get a positive result. Now that nitrite has entered the equation, you need to make sure you are dosing with enough Prime to protect your fish from both ammonia and nitrites. Fortunately, working out your new dosage is pretty simple – just add your nitrite and ammonia readings together. Let’s say your test returns the following… Ammonia 0.25 ppm Nitrite 1.5 ppm Adding the two together will give you a total of 1.75 ppm. A double dose of Prime will take care of it. This time, if your combined ppm of ammonia and nitrite reaches 4, perform a 50% water change. Keep repeating this. You will eventually notice that your ammonia drops to zero. This is a good thing – bacteria are eating the ammonia as quickly as it is being produced, resulting in a zero reading. Continue daily dosing and testing for ammonia and nitrites. Once your nitrite levels stop rising as quickly, you are ready for the next step. Step 6: Nitrates appear Now, you want to test for nitrates. If none are present, keep repeating the previous step and testing for nitrates daily until you get a positive result. Once nitrates are present, you are nearing the end (woohoo!). Continue testing for ammonia, nitrites and nitrates. Your ammonia levels should still be zero, and your nitrite levels should be declining. Keep dosing with Prime until both your nitrite and ammonia levels are zero. At this stage, the beneficial bacteria are eating them as quickly as they are being produced. Congratulations! You have successfully completed a fish-in cycle. ... show more
Reviewed in the United States on May 2, 2021 by Cory Cory

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