Marine & Freshwater

(42 results)
Seachem® Prime® Aquarium Water Conditioner
4 sizes
(359)
$3.79 - $16.69
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Seachem® Stability® New Tank Stabilization System Aquarium Water Conditioner
2 sizes
(190)
$3.99 - $8.39
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Seachem® Purigen® Premium Synthetic Absorbent
2 sizes
(54)
$9.19 - $15.69
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Seachem® Flourish Excel™
(10)
$7.89
$11.99
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Seachem® Matrix™
3 sizes
(20)
$5.29 - $35.09
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Seachem® The Bag ™ Welded Filter
(4)
$6.07
$9.99
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Seachem® Clarity™
(16)
$8.69
$14.99
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Seachem® Purigen®
(10)
$62.99
$115.31
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Seachem® Stability®
2 sizes
(8)
$54.99 - $77.09
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Seachem® Alert Combo™ Aquarium pH & Ammonia Detector
(76)
$15.49
$18.99
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Seachem® Reef Strontium™
(0)
$7.09
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Seachem® Reef Iodide™
2 sizes
(0)
$8.39 - $10.19
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Seachem® Reef Advantage Magnesium™
2 sizes
(0)
$6.09 - $22.79
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Seachem® Reef Plus™
2 sizes
(0)
$7.29 - $10.69
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Seachem® Reef Buffer™
2 sizes
(0)
$7.19 - $21.00
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Seachem® Reef Fusion 2™
2 sizes
(0)
$8.59 - $20.19
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Seachem® Reef Fusion 1™
2 sizes
(0)
$8.59 - $12.99
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Seachem® Reef Status Calcium Kit
(0)
$34.49
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Seachem® Reef Carbonate™
2 sizes
(0)
$6.39 - $6.89
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SeaChem Reef Complete Marine Care
(0)
$7.09
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Seachem® PhosGuard™
(3)
$4.89
$7.69
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Seachem® CupriSorb™ - Copper & Heavy Metal Absorbent
(0)
$6.99
$14.99
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Seachem® Matrix Carbon™
(0)
$6.07
$9.99
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Seachem Flourish Potassium™
(6)
$9.39
$11.99
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Seachem® Flourish Excel™
2 sizes
(2)
$36.49 - $66.79
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Seachem® Flourish®
(4)
$36.49
$39.89
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Seachem® Prime®
2 sizes
(5)
$52.99 - $88.99
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Seachem® Phosguard™
2 sizes
(4)
$32.30 - $60.99
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Seachem® Tidal™ 75 Zeolite Filter Pouch
(0)
$8.19
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Seachem® Tidal™ 110 MatrixCarbon
(0)
$17.79
$20.99
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Seachem® Tidal™ 75 Matrix Carbon
(0)
$10.19
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Seachem® Tidal Matrix™
(0)
$7.69
$12.29
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Seachem® Tidal Matrix™
(2)
$7.69
$11.29
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Seachem® Tidal ™
(0)
$9.99
$16.88
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Seachem® Tidal ™
(0)
$6.99
$10.99
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Seachem® Tidal ™
(0)
$9.99
$11.69
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Seachem® Marine Buffer™
(0)
$23.19
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Seachem® Reef Complete™
(0)
$10.59
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Seachem® Tidal™ Zeolite
(0)
$13.49
$14.99
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Seachem® Marine Buffer
(2)
$9.99
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Explore Our Extensive Range of Fish Supplies 

At PetSmart, we offer a comprehensive selection of supplies for both freshwater and marine fish enthusiasts. Whether you're setting up a new aquarium or maintaining an existing one, our range of products ensures your aquatic pets thrive. From aquarium decor to essential maintenance tools, find everything you need to create a vibrant underwater world. 

Freshwater and Marine Fish Supplies 

Our collection includes a variety of aquarium accessories and pet fish supplies designed to cater to the unique needs of both freshwater and marine environments. Explore our selection of aquarium decor to enhance the beauty of your tank, and discover top-quality marine aquarium supplies to support the health of your aquatic life. 

Essential Aquarium Maintenance 

Maintaining a healthy aquarium requires the right tools and knowledge. Our range of aquarium maintenance products includes everything from filters to water conditioners, ensuring your tank remains a safe and clean environment for your fish. Learn how to maintain pH levels and keep your aquarium filter running efficiently with our expert tips. 

Frequently Asked Questions (FAQs) 

What maintenance does a fish tank need? 
Regular maintenance is crucial for a healthy aquarium. This includes cleaning the tank, changing the water, and checking the filter and pH levels. 
Can I put tap water in my fish tank? 
Tap water can be used in your fish tank, but it should be treated with a water conditioner to remove harmful chemicals like chlorine. 
Should an aquarium filter be on all the time? 
Yes, an aquarium filter should run continuously to maintain water quality and provide a healthy environment for your fish. 
How to maintain pH level in an aquarium? 
To maintain the pH level in your aquarium, regularly test the water and use pH adjusters as needed. Consistent water changes also help stabilize pH levels.