API STRESS ZYME Aquarium Cleaning Solution, 946 ml for Freshwater and Saltwater Tanks

API STRESS ZYME is a freshwater and saltwater aquarium cleaning solution that uses over 300 million live bacteria per teaspoonful to consume sludge and organic debris in a 32-ounce (946 mL) bottle.

• Over 300 million live bacteria per teaspoonful — helps break down sludge and organic debris.
• For freshwater and saltwater aquariums — supports routine cleaning across both aquarium types.
• Weekly use — helps maintain a strong biological filter and reduce maintenance over time.
• Works on aquarium sludge and debris — helps keep gravel, glass and decorations clean.
• 32-ounce (946 mL) bottle — provides aquarium cleaning solution for regular maintenance.

Fish waste, uneaten food and other organic material can build up in an aquarium and become difficult to remove, especially from gravel, rock and coral. STRESS ZYME is made for routine aquarium care, helping aquarists manage this organic debris as part of a weekly maintenance schedule.

What does API STRESS ZYME do in an aquarium?

Its live bacteria consume sludge and organic debris, helping keep gravel and glass clean naturally. By adding beneficial bacteria, the solution also helps boost the aquarium’s natural cycle and maintain a strong biological filter. Organic buildup can contribute to harmful water conditions, including ammonia and nitrite problems, so regular debris management is part of aquarium upkeep.

• Targets sludge and organic debris in the aquarium.
• Supports the natural aquarium cycle and biological filtration.

How often should I use API STRESS ZYME?

Use it weekly to help maintain a clean, healthy aquarium and a strong biological filter. Follow product directions when using it; the bacteria count per teaspoonful describes the solution, not a dosing instruction.

• Designed for recurring aquarium maintenance.
• Helps reduce maintenance over time by consuming organic debris.

Which aquariums and fish is this solution for?

API STRESS ZYME is made for freshwater and saltwater aquariums. It suits routine care for tanks with fish such as tropical community fish, cichlids and goldfish, and can be part of a broader API aquarium-care routine; API aquarium treatment supplies are designed to work in conjunction with one another.

• Freshwater aquarium use.
• Saltwater aquarium use.
• API has spent over 50 years creating research-driven aquarium-care solutions.

This solution is a practical fit for aquarium owners who want to manage sludge and organic debris through regular biological maintenance rather than relying only on manual removal. It is intended for weekly care in freshwater and saltwater aquariums, not as a substitute for following aquarium product directions. For fishkeepers maintaining community fish, cichlids, goldfish or other aquarium inhabitants, its role is clear: live bacteria help consume debris and support the aquarium’s biological filter.