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Fluval

Fluval in Line UVC Clarifier for Aquarium Filters

  • Based on 1,878 reviews
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Availability: Only 7 left in stock, order soon!
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Arrives Sunday, Sep 27
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Features

  • Powerful UV Sterilizer For Aquariums: The Fluval in-line UVC clarifier eliminates algae, bacteria, and cloudiness, providing crystal-clear water. This aquarium UV sterilizer is safe for fish and plants, reducing green water and improving tank health. Keep your fish happy and healthy
  • Versatile UV Filter Aquarium System: Designed for use with most 5/8" filter hoses, this fish tank UV sterilizer easily integrates into your setup. Whether you have a freshwater or saltwater tank, this UV sterilizer aquarium device keeps water clean and clear for vibrant aquatic life
  • Safe & Effective Aquarium UV Light Sterilizer: Unlike chemical treatments, this aquarium UV sterilizer works naturally by breaking down harmful bacteria and algae. This UV aquarium sterilizer helps prevent disease outbreaks while maintaining a safe and healthy environment for fish and plants
  • Easy Installation & Low Maintenance: This UV filter aquarium clarifier features a compact design for hassle-free setup. Connect it to your 5/8 filter hose, and you're ready to go. The easy-to-remove bulb allows quick replacement, making this UV sterilizer for aquariums simple to maintain
  • Enhance Tanks Water Quality: This fish tank UV sterilizer removes harmful microorganisms that can make your water cloudy. By using this UV aquarium sterilizer, your tank will have clearer water, healthier fish, and improved water circulationperfect for any aquarium enthusiast

Description

Keep your aquarium water crystal clear with the Fluval In-Line UVC Clarifier, a powerful UV sterilizer for aquariums that eliminates green water. Designed for use with most 5/8” filter hoses, this aquarium UV sterilizer is easy to install and maintain, ensuring a cleaner and healthier tank environment. Its UV filter aquarium technology effectively removes cloudiness while being safe for fish and plants. Unlike chemical treatments, this fish tank UV sterilizer works naturally, reducing green water and preventing disease outbreaks. The UV aquarium sterilizer features a compact design, making integration with your current filter system seamless. Plus, the easy-to-remove aquarium UV light sterilizer bulb ensures low maintenance. Keep your aquatic environment thriving with this UV sterilizer for aquariums and enjoy the beauty of a pristine, algae-free tank!

Brand: Fluval


Item Weight: 15.8 ounces


Item Form: Stick


Unit Count: 1 Count


Manufacturer: Rolf C. Hagen (USA) Corp.


Product Dimensions ‏ : ‎ 6.3 x 2.36 x 5.12 inches; 15.8 ounces


Item model number ‏ : ‎ A203


Date First Available ‏ : ‎ October 6, 2020


Manufacturer ‏ : ‎ Rolf C. Hagen (USA) Corp.


Best Sellers Rank: #29,075 in Pet Supplies (See Top 100 in Pet Supplies) #280 in Aquarium Filter Accessories


#280 in Aquarium Filter Accessories:


Customer Reviews: 4.5 4.5 out of 5 stars (1,878)


Brand Name: Fluval


Unit Count: 1 Count


Manufacturer: Rolf C. Hagen (USA) Corp.


UPC: 015561102032 015561102261


Number of Items: 1


Included Components: All items listed in description.


Item Type Name: Aquarium UVC Filter Accessory


Model Number: A203


Manufacturer Part Number: A203


Warranty Description: 2 Year Standard Warranty, The Fluval UVC in-line Clarifier is guaranteed for defective parts and workmanship for a period of 2 years from the date of purchase. This guarantee is valid with proof of purchase only. The guarantee is limited to repair or replacement only and does not cover consequential loss, loss or damage to livestock and personal property or damage to animate or objects, irrespective of the cause thereof. This guarantee is valid only under normal operating conditions for which the unit is intended. It excludes any damage caused by unreasonable use, negligence, improper installation, tampering, abuse or commercial use. The warranty does not cover wear and tear, breakage of glass or parts which have not been adequately or correctly maintained. THIS DOES NOT AFFECT YOUR STATUTORY RIGHTS.


Item Weight: 15.8 ounces


Item Form: Stick


Pet Type: Fish


Target Species: Fish


Allergen Information: Allergen-Free


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Sep 27

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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Similar Products

Top Amazon Reviews

    • Helps keep water clear, bulb is replaceable
Review Image by S. H.
If you have fluval filter I recommend this. Helps keep water clear. You can now replace the bulb making this a better value at the same price. Installation is easy. Built in timer a plus.
Reviewed in the United States on June 14, 2026 by S. H.
    • Excellent Clarity
The Fluval in Line UVC Clarifier made my aquarium look really good. I was very skeptical at first, but after seeing the clarity in my aquarium, I bought another one for my other aquarium. I would recommend this product.
Reviewed in the United States on June 14, 2026 by Marc
    • Works amazingly well.
Was not sure how good this would work, was pleasantly surprised how well it did. Purposely put it on when the tank was pretty bad, even on a lower setting it really made a difference. Once I changed the water and cleaned my filter it really kept the tank cleaner. Need to buy one for my smaller tank now. Only wish it had warning when the bulb goes out like some have. But happy with the purchase anyway. ... show more
Reviewed in the United States on May 26, 2026 by Darrin Wendland
    • Easy to Attach UV Stabilizer
easy to attach, Im ready to invest in some very expensive fresh water fish. Trying to have the tank set, going to wait a couple weeks to purchase the fish (Discuss) Good investment for a 75-gallon tank.
Reviewed in the United States on March 21, 2026 by Marvin l. Kelley
    • High Quality Just make sure it is for your system!
Even though I was unfortunately unable to use the Fluval In-Line UVC Clarifier due to compatibility issues with my setup, I still wanted to leave a positive review based on the product’s design, quality, and reputation. When I first received it, I was impressed with how well-made and compact it is. The materials feel durable, and the instructions were clear and easy to follow. I’ve read so many positive experiences from other aquarium owners who saw dramatic improvements in water clarity after installing this unit, which was the main reason I purchased it. Unfortunately, my filter hoses were not the right size for this particular model, so I couldn’t install it on my system. That’s my own oversight, not a fault of the product itself. If your setup is compatible, I have no doubt this clarifier would work well, especially for green water and cloudy water issues. Although I had to return it, I would still recommend it to other aquarium owners who want an easy, in-line solution for keeping their tanks clear. Just be sure to check your hose size before purchasing! ... show more
Reviewed in the United States on March 1, 2025 by MadeYouShart
    • The shape of this UV light is awesome
I have owned several UV lights for my fish tank. This one works well, was the easiest to mount due to its shape and although time will tell, I expect it to last a good long while. I have to emphasize, the shape makes it extremely easy to mount under the cabinet there it quickly becomes cramped with all the equipment in it (canister filter, heater, UV light, power strip, a dozen electric cables, hoses... you get the idea). ... show more
Reviewed in the United States on February 20, 2026 by Jerzee
    • Will prevent pathogenic and algae blooms.
Review Image by Steven
Review Image by Steven
Review Image by Steven
After repeated algae blooms and cloudy water from pathogens, I got this Fluval UV water sterilizer. I had 1/2" filter inlet/outlet pipes so I had to use 1/2“X5/8“ nylon hose barb adapters because the Fluval 207 uses 5/8“ ID vinyl. I checked the unit before install to make sure the light was coming on, keep that in mind. Update: Well, it has been almost a week with the UV light on for 10 hrs a day. I started with 8 hrs a day, but bumped it up to 10 hrs before I started seeing the water become clearer. So just about a week for the water to become crystal clear. I noticed some change after a day. Best money I could have spent as this will kill pathogens in the water that can cause disease, I can even notice the fish become more active. The water almost looks so clear like it was being filtered with a diatom filter. The video is looking long ways through the tank. ... show more
Reviewed in the United States on April 30, 2024 by Steven
    • Clear water!
Cleared my 75 gallon tank right up! I had 8 fat goldfish in this tank with a Fluval 407 and the water was a constant cloudy green. Invested in this and everything has been great since!
Reviewed in the United States on January 27, 2026 by Ali Wales

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