Koi Shield – Protective Treatment for Koi and Ornamental Fish
Koi Shield is a versatile, aquarium-grade treatment formulated to protect and restore the health of koi and ornamental fish. Designed for serious koi keepers, it serves as a reliable first line of defense against fungal infections, external parasites, and chemical toxicities that commonly affect stressed or compromised fish.
From protecting fish eggs to supporting recovery in sick or recently transported koi, Koi Shield is an essential tool for maintaining fish health in quarantine, hospital, and controlled pond systems.
What Koi Shield Is Used For
Koi Shield is intended to support fish health by addressing:
Fungal infections on skin, fins, and eggs
External parasite stress
Chemical toxicity and environmental stress
Recovery after transport, handling, or illness
Its broad utility makes it especially valuable during quarantine and recovery phases.
Why Choose Koi Shield
Aquarium-Grade Quality
Formulated to professional standards for predictable, controlled use.
Broad Protective Use
Effective for fungal issues, parasite stress, and chemical exposure.
Egg-Safe Application
Suitable for treating fish eggs to help prevent fungal growth.
Recovery Support
Helps stabilize fish during periods of stress, transport, or illness.
Product Strength and Coverage
Net contents: 50 g
Coverage: Treats up to 5,000 gallons
How to Use Koi Shield
Dosage
Dose 1 gram per 100 gallons of water.
Application
Dissolve the measured powder in a small container of water.
Distribute evenly throughout the tank or system.
Aeration
Maintain strong aeration during treatment, as methylene blue can reduce dissolved oxygen levels.
Treatment Duration
Leave the treatment in the water for 24–48 hours.
After treatment, a 10–20% partial water change may be performed to reduce residual product.
The compound naturally degrades over time.
Koi Shield is best used in quarantine tanks, hospital systems, or other controlled environments.
Pond / Tank Size Dosage Chart
| Water Volume |
Dose |
| 50 gallons |
0.5 g |
| 100 gallons |
1 g |
| 250 gallons |
2.5 g |
| 500 gallons |
5 g |
| 1,000 gallons |
10 g |
Adjust proportionally for larger systems.
Safety and Handling
For ornamental fish use only
Not for fish intended for human consumption
Maintain strong aeration during use
Store in a cool, dry location
Keep out of reach of children and pets
Frequently Asked Questions – Koi Shield
What type of treatment is Koi Shield?
Koi Shield is a methylene blue–based treatment used to protect koi and ornamental fish from fungal infections, parasite stress, and chemical exposure.
Can Koi Shield be used on fish eggs?
Yes. Koi Shield is suitable for protecting fish eggs against fungal growth.
How long should Koi Shield remain in the water?
Leave the treatment in place for 24–48 hours, followed by a partial water change if desired.
Is aeration required?
Yes. Strong aeration is important during treatment because methylene blue can reduce dissolved oxygen levels.
Can Koi Shield be used in a main pond?
It is best used in quarantine tanks, hospital systems, or controlled environments where dosing and aeration can be carefully managed.
