10 Best Freshwater Aquarium Water Treatments 2025: According to Reviews | Chewy

The 10 Best Freshwater Aquarium Water Treatments

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How we created this freshwater aquarium water treatment list

We leveraged input from our veterinarians and artificial intelligence to identify key considerations to help you find the best freshwater aquarium water treatment.
We scanned thousands of customer reviews and ratings and scored each product based on its performance against each of the key considerations. We then considered how popular a product is with Chewy customers and combined that with its key consideration scores to create the list of the best freshwater aquarium water treatments.

Key freshwater aquarium water treatment considerations

Compatibility

Ease of Use

Effectiveness

Long-Term Results

1
API Stress Coat Aquarium Water Conditioner, 16-fl oz bottle
API Stress Coat Aquarium Water Conditioner, 16-fl oz bottle
API Stress Coat Aquarium Water Conditioner, 16-fl oz bottle
API Stress Coat Aquarium Water Conditioner, 16-fl oz bottle
API Stress Coat Aquarium Water Conditioner, 16-fl oz bottle
API Stress Coat Aquarium Water Conditioner, 16-fl oz bottle

API Stress Coat Aquarium Water Conditioner, 16-fl oz bottle

Rated 4.8 out of 5 stars
671
$10.99Chewy Price
($0.69/fl oz)
Promo, New Customers Only: Spend $49+, Get $20 eGift Card

Our ratings

Compatibility

4.5/5
Great

Ease of Use

4.5/5
Great

Effectiveness

4.6/5
Excellent

Long-Term Results

4.6/5
Excellent

Is this freshwater aquarium water treatment right for my pet?

Aquarium Type

Freshwater, Saltwater

Fish Type

Tropical Freshwater, Betta, Cichlid, Goldfish...

Health Feature

Anti-Fungal / Anti-Bacterial
2
Tetra AquaSafe Plus Freshwater & Marine Aquarium Water Conditioner, 33.8-fl oz bottle
Tetra AquaSafe Plus Freshwater & Marine Aquarium Water Conditioner, 33.8-fl oz bottle
Tetra AquaSafe Plus Freshwater & Marine Aquarium Water Conditioner, 33.8-fl oz bottle
Tetra AquaSafe Plus Freshwater & Marine Aquarium Water Conditioner, 33.8-fl oz bottle
Tetra AquaSafe Plus Freshwater & Marine Aquarium Water Conditioner, 33.8-fl oz bottle
Tetra AquaSafe Plus Freshwater & Marine Aquarium Water Conditioner, 33.8-fl oz bottle
Tetra AquaSafe Plus Freshwater & Marine Aquarium Water Conditioner, 33.8-fl oz bottle
Tetra AquaSafe Plus Freshwater & Marine Aquarium Water Conditioner, 33.8-fl oz bottle
Tetra AquaSafe Plus Freshwater & Marine Aquarium Water Conditioner, 33.8-fl oz bottle

Tetra AquaSafe Plus Freshwater & Marine Aquarium Water Conditioner, 33.8-fl oz bottle

Rated 4.8 out of 5 stars
357
$12.26Chewy Price
($0.37/fl oz)
Promo, New Customers Only: Spend $49+, Get $20 eGift Card

Our ratings

Compatibility

4.6/5
Excellent

Ease of Use

4.7/5
Excellent

Effectiveness

4.7/5
Excellent

Long-Term Results

4.6/5
Excellent

Is this freshwater aquarium water treatment right for my pet?

Aquarium Type

Freshwater, Saltwater

Fish Type

Tropical Freshwater, Marine Fish
3
API Tap Water Conditioner, 16-fl oz bottle
API Tap Water Conditioner, 16-fl oz bottle
API Tap Water Conditioner, 16-fl oz bottle
API Tap Water Conditioner, 16-fl oz bottle
API Tap Water Conditioner, 16-fl oz bottle
API Tap Water Conditioner, 16-fl oz bottle

API Tap Water Conditioner, 16-fl oz bottle

Rated 4.8 out of 5 stars
430
$8.45Chewy Price
($0.53/fl oz)
Promo, New Customers Only: Spend $49+, Get $20 eGift Card

Our ratings

Compatibility

4.5/5
Great

Ease of Use

4.5/5
Great

Effectiveness

4.6/5
Excellent

Long-Term Results

4.5/5
Great

Is this freshwater aquarium water treatment right for my pet?

Aquarium Type

Freshwater, Saltwater

Fish Type

Tropical Freshwater, Cichlid, Betta, Goldfish...
4
Acurel F Aquarium Water Clarifier, 50-mL bottle

Acurel F Aquarium Water Clarifier, 50-mL bottle

Rated 4.6 out of 5 stars
133
$8.99Chewy Price
Promo, New Customers Only: Spend $49+, Get $20 eGift Card

Our ratings

Compatibility

4.6/5
Excellent

Ease of Use

4.3/5
Great

Effectiveness

4.4/5
Great

Long-Term Results

4.4/5
Great

Is this freshwater aquarium water treatment right for my pet?

Aquarium Type

Freshwater

Fish Type

Tropical Freshwater, Betta, Cichlid, Goldfish
5
Fritz Zyme 7 Freshwater Nitrifying Bacteria for Aquariums, 32-fl oz bottle

Fritz Zyme 7 Freshwater Nitrifying Bacteria for Aquariums, 32-fl oz bottle

Rated 4.6 out of 5 stars
107
$19.99Chewy Price
($0.63/fl oz)
Promo, New Customers Only: Spend $49+, Get $20 eGift Card

Our ratings

Compatibility

4.3/5
Great

Ease of Use

4.6/5
Excellent

Effectiveness

4.4/5
Great

Long-Term Results

4.5/5
Great

Is this freshwater aquarium water treatment right for my pet?

Aquarium Type

Freshwater

Fish Type

Tropical Freshwater

Health Feature

Anti-Fungal / Anti-Bacterial
6
SunGrow Betta Fish Indian Almond Leaves, Water Conditioner & Tank Treatment for Freshwater Aquarium
SunGrow Betta Fish Indian Almond Leaves, Water Conditioner & Tank Treatment for Freshwater Aquarium
SunGrow Betta Fish Indian Almond Leaves, Water Conditioner & Tank Treatment for Freshwater Aquarium
SunGrow Betta Fish Indian Almond Leaves, Water Conditioner & Tank Treatment for Freshwater Aquarium
SunGrow Betta Fish Indian Almond Leaves, Water Conditioner & Tank Treatment for Freshwater Aquarium
SunGrow Betta Fish Indian Almond Leaves, Water Conditioner & Tank Treatment for Freshwater Aquarium

SunGrow Betta Fish Indian Almond Leaves, Water Conditioner & Tank Treatment for Freshwater Aquarium

Rated 4.5 out of 5 stars
139
$6.93Chewy Price
Promo, New Customers Only: Spend $49+, Get $20 eGift Card

Our ratings

Compatibility

4.4/5
Great

Ease of Use

4.5/5
Great

Effectiveness

4.4/5
Great

Long-Term Results

4.4/5
Great

Is this freshwater aquarium water treatment right for my pet?

Material

Plant Material

Aquarium Type

Freshwater, Saltwater

Fish Type

Betta, Goldfish, Cichlid, Tropical Freshwater...

Health Feature

Anti-Fungal / Anti-Bacterial, Reproduction & Nursing
7
Fluval Plant & Shrimp Stratum Plant Care, 4.4-lb bag
Fluval Plant & Shrimp Stratum Plant Care, 4.4-lb bag
Fluval Plant & Shrimp Stratum Plant Care, 4.4-lb bag
Fluval Plant & Shrimp Stratum Plant Care, 4.4-lb bag
Fluval Plant & Shrimp Stratum Plant Care, 4.4-lb bag
Fluval Plant & Shrimp Stratum Plant Care, 4.4-lb bag
Fluval Plant & Shrimp Stratum Plant Care, 4.4-lb bag
Fluval Plant & Shrimp Stratum Plant Care, 4.4-lb bag
Fluval Plant & Shrimp Stratum Plant Care, 4.4-lb bag

Fluval Plant & Shrimp Stratum Plant Care, 4.4-lb bag

Rated 4.6 out of 5 stars
102
$15.28Chewy Price
($3.48/lb)
Promo, New Customers Only: Spend $49+, Get $20 eGift Card

Our ratings

Compatibility

4.3/5
Great

Ease of Use

4.4/5
Great

Effectiveness

4.6/5
Excellent

Long-Term Results

4.4/5
Great

Is this freshwater aquarium water treatment right for my pet?

Aquarium Type

Nano Tank, Freshwater

Fish Type

Freshwater Invertebrate, Tropical Freshwater
8
CaribSea Eco-Complete Planted Aquarium Substrate, Black, 20-lb bag
CaribSea Eco-Complete Planted Aquarium Substrate, Black, 20-lb bag
CaribSea Eco-Complete Planted Aquarium Substrate, Black, 20-lb bag

CaribSea Eco-Complete Planted Aquarium Substrate, Black, 20-lb bag

Rated 4.4 out of 5 stars
127
$35.99Chewy Price
($1.80/lb)
Promo, New Customers Only: Spend $49+, Get $20 eGift Card

Our ratings

Compatibility

4.3/5
Great

Ease of Use

4.6/5
Excellent

Effectiveness

4.5/5
Great

Long-Term Results

4.7/5
Excellent

Is this freshwater aquarium water treatment right for my pet?

Material

Stone

Aquarium Type

Freshwater, Saltwater

Fish Type

Goldfish, Tropical Freshwater, Betta, Bottom Feeder...
9
Aqueon Aquarium Water Clarifier, 16-fl oz bottle
Aqueon Aquarium Water Clarifier, 16-fl oz bottle
Aqueon Aquarium Water Clarifier, 16-fl oz bottle
Aqueon Aquarium Water Clarifier, 16-fl oz bottle
Aqueon Aquarium Water Clarifier, 16-fl oz bottle
Aqueon Aquarium Water Clarifier, 16-fl oz bottle

Aqueon Aquarium Water Clarifier, 16-fl oz bottle

Rated 4.5 out of 5 stars
82
$6.18Chewy Price
($0.39/fl oz)
Promo, New Customers Only: Spend $49+, Get $20 eGift Card

Our ratings

Compatibility

4.4/5
Great

Ease of Use

4.6/5
Excellent

Effectiveness

4.5/5
Great

Long-Term Results

4.4/5
Great

Is this freshwater aquarium water treatment right for my pet?

Aquarium Type

Freshwater

Fish Type

Tropical Freshwater
10
API Freshwater Aquarium Master Test Kit, 800 count
API Freshwater Aquarium Master Test Kit, 800 count
API Freshwater Aquarium Master Test Kit, 800 count
API Freshwater Aquarium Master Test Kit, 800 count
API Freshwater Aquarium Master Test Kit, 800 count
API Freshwater Aquarium Master Test Kit, 800 count
API Freshwater Aquarium Master Test Kit, 800 count

API Freshwater Aquarium Master Test Kit, 800 count

Rated 4.7 out of 5 stars
299
$35.98Chewy Price
($0.05/ea)
Promo, New Customers Only: Spend $49+, Get $20 eGift Card

Our ratings

Compatibility

4.8/5
Excellent

Ease of Use

4.8/5
Excellent

Effectiveness

4.8/5
Excellent

Long-Term Results

4.7/5
Excellent

Is this freshwater aquarium water treatment right for my pet?

Aquarium Type

Freshwater

Fish Type

Tropical Freshwater, Cichlid, Goldfish, Betta...