Seachem Stability® – 250 mL
Seachem Stability® 250 mL is a concentrated beneficial bacteria supplement designed to help establish and maintain biological filtration in freshwater and saltwater aquariums.
Stability® contains a blend of bacterial strains selected to function across a broad range of aquarium conditions. It is useful when starting a new aquarium, adding livestock, performing water changes, maintaining biological filtration, or supporting the biofilter during periods of change.
Key Features
- Helps establish biological filtration
- Suitable for new and established aquariums
- For freshwater and saltwater systems
- May be used when introducing new fish
- Useful following routine water changes
- Helps support the aquarium biofilter
- Can be used when aquarium medications are being used
- 250 mL standard-size bottle
Product Information
- Brand: Seachem
- Product: Stability®
- Size: 250 mL
- Product Type: Beneficial bacteria / biological filtration supplement
- Use: Freshwater and saltwater aquariums
What Does Seachem Stability® Do?
Stability® introduces beneficial bacterial strains that help establish and maintain the biological filtration system of an aquarium.
A healthy biofilter helps process waste produced by fish, uneaten food, and other organic material through the aquarium's nitrogen cycle.
Stability® can be particularly useful when:
- Starting a new aquarium
- Adding new livestock
- Performing water changes
- Adding or replacing biological filter media
- Cleaning or servicing filtration
- Using aquarium medications
- Supporting an established biological filter
Directions for a New Aquarium
Shake well before use.
Seacheam recommends the following startup dosage:
- Day 1: Use 5 mL for every 10 gallons of aquarium water.
- Days 2–7: Use 5 mL for every 20 gallons once daily.
Turn off UV sterilizers and ozone while Stability® is being used.
New Aquarium Dosage Examples
| Aquarium Size | Day 1 | Days 2–7 |
|---|---|---|
| 10 Gallons | 5 mL | 2.5 mL daily |
| 20 Gallons | 10 mL | 5 mL daily |
| 40 Gallons | 20 mL | 10 mL daily |
| 55 Gallons | 27.5 mL | 13.75 mL daily |
| 75 Gallons | 37.5 mL | 18.75 mL daily |
Routine Maintenance Dosage
For ongoing biological filtration support, Seachem recommends:
5 mL for every 20 gallons
Use once monthly or when:
- Performing a water change
- Introducing new fish
- Medicating the aquarium
- Supporting the biofilter after maintenance
Can Fish Be Added While Using Stability®?
Seachem states that fish and other aquatic livestock may be introduced while Stability® is being used as long as the recommended seven-day dosage is maintained.
Even when bacterial supplements are used, ammonia and nitrite should still be monitored closely in new or recently disturbed aquariums.
Does Stability® Instantly Cycle an Aquarium?
Stability® helps establish beneficial bacteria, but aquariums do not all cycle at the same rate.
Seachem notes that many aquariums may still require approximately 4–6 weeks to become fully cycled. Continue testing ammonia and nitrite rather than assuming the aquarium is fully established after the initial dosing period.
Using Stability® for Fishless Cycling
When performing a fishless cycle, an ammonia source is still required to feed the developing bacterial population.
Continue monitoring:
- Ammonia
- Nitrite
- Nitrate
The aquarium should be considered cycled only after testing confirms that the biological filter can consistently process the available ammonia and nitrite.
Freshwater and Saltwater Use
Stability® can be used in both freshwater and marine aquariums.
Suitable applications include:
- Freshwater community aquariums
- Planted aquariums
- Cichlid aquariums
- Goldfish aquariums
- Shrimp and snail aquariums
- Marine fish aquariums
- Reef aquariums
- Quarantine and holding tanks
Using Stability® After Adding Fish
Adding fish increases the biological load on an aquarium. Stability® can be added when new livestock is introduced to help support the biofilter as it adjusts to the increased waste load.
Continue monitoring ammonia and nitrite after adding livestock, especially in newer aquariums.
Using Stability® After a Water Change
Stability® may be used after routine water changes as part of ongoing biofilter maintenance.
Seachem recommends 5 mL per 20 gallons for routine maintenance.
Using Stability® With Medications
Seachem recommends Stability® when medicating an aquarium as part of maintaining biological filtration.
Always follow the directions for both Stability® and the specific medication being used.
UV Sterilizers and Ozone
Seachem recommends turning off UV sterilizers and ozone while Stability® is being dosed.
Normal biological and mechanical filtration should remain operating so beneficial bacteria have surfaces on which to establish.
Important Use Notes
- Shake well before use.
- Turn off UV sterilization and ozone during dosing.
- Continue normal filtration and aeration.
- Monitor ammonia and nitrite when cycling a new aquarium.
- Do not rely on bacterial supplements as a substitute for water testing.
- Maintain appropriate stocking and feeding levels.
- Perform water changes when water quality requires them.
Frequently Asked Questions
What is Seachem Stability® used for?
It is a beneficial bacteria supplement designed to help establish and maintain biological filtration in freshwater and saltwater aquariums.
How much Stability® should I use on Day 1?
Use 5 mL for every 10 gallons of aquarium water.
How much should I use after Day 1?
Use 5 mL for every 20 gallons daily for the remainder of the seven-day startup period.
Can I add fish while using Stability®?
Yes. Seachem states that aquatic livestock may be introduced while Stability® is being used as long as the recommended dosage is maintained.
Does Stability® instantly cycle the aquarium?
No. It helps establish beneficial bacteria, but every aquarium cycles differently. Continue testing ammonia and nitrite until the biofilter is fully established.
Can Stability® be used after water changes?
Yes. Seachem recommends it with water changes as part of routine biofilter maintenance.
Can it be used in saltwater aquariums?
Yes. Stability® is designed for freshwater and marine systems.
Should I turn off my UV sterilizer?
Yes. Seachem recommends turning off UV sterilization and ozone during use.
Available at Tropical Treasures Wyo
Seachem Stability® 250 mL is available at Tropical Treasures Wyo in Cheyenne, Wyoming, when in stock.
Eligible dry goods are available for shipping.
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