Seachem Cupramine Copper 100ml — Buffered Copper Treatment for Freshwater & Marine Fish

Overview

Seachem Cupramine Copper 100ml is a carefully buffered copper formulation designed to target external parasites on fish in both freshwater and saltwater aquariums. It improves upon traditional copper sources by staying in solution, reducing acidity, and minimizing disruption to the filter bed. This makes Cupramine a practical option for hobbyists who want a targeted, controllable parasite treatment without broad water chemistry swings.

Key advantages

• Buffered active copper that helps protect delicate gill tissues
• Effective against external parasites such as Oodinium, Cryptocaryon, Amyloodinium, and Ichthyophthirius
• Suitable for marine and freshwater use
• Non-acidic formulation, with lower observed fish toxicity
• Remains in solution, reducing concentration fluctuations in the water column
• Does not contaminate the filter bed, preserving filter media integrity
• Fully charged ionic copper, active at low concentrations
• Easy removal with carbon filtration or other chemical filtration after treatment

Treatment window and safety margins

There is more than a four-fold gap between the minimal therapeutic dose (about 0.2 mg/L) and the toxic level (around 0.8 mg/L). This broad window can offer flexibility for treatment planning, but it’s important to monitor copper levels and follow label directions to protect fish and tank inhabitants.

Freshwater and marine compatibility

Cupramine is designed for use in both freshwater and marine systems and is recommended for treating certain external diseases in fish-only setups. It is not suitable for tanks housing invertebrates, corals, crustaceans, or elasmobranchs (sharks and rays). This makes it important to match the product to your tank residents before use.

Usage considerations

• Follow the label directions for dosing to maintain safety margins
• During treatment, copper can be removed from the water with carbon filtration once the course ends
• After treatment, consider additional chemical filtration or carbon to help remove residual copper
• Avoid mixing with invertebrate-tank residents or highly sensitive species

Real-life use scenarios

Home aquarists report visible improvements in fish behavior and coloration as external parasites recede, with calmer gill movement and steadier activity. In mixed-species tanks, careful dosing and monitoring can help balance parasite control with overall tank health.

What to expect for your tank

Cupramine provides a targeted approach to parasite control, with the benefit of being removable and less disruptive to routine filtration. While results can vary by tank, many hobbyists experience a smoother path to healthier-looking fish when using cupramine as directed and avoiding incompatible tank mates.