| Management number | 234590584 | Release Date | 2026/07/02 | List Price | US$3.71 | Model Number | 234590584 | ||
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PolyGuard™ is the single most effective medication to keep freshwater fish free of disease! It is an effective treatment and safeguard against all prevalent bacterial, fungal, and parasitic diseases of exotic fish. For use in freshwater or marine aquaria.
When our pets are sick, we immediately want to reach for the most powerful medication on the shelf. However, sometimes the right choice to prevent stress is to opt for a gentler medication at first, especially with less severe infections. PolyGuard is among Seachem’s strongest medications, and is best used when you are unsure what disease you are treating or when the fish is suffering from multiple infections.
Active ingredients: sulfathiazole (36%), malachite green (1.9%), nitrofurantoin (0.14%), nitrofural (0.14%), quinacrine dihydrochloride (0.27%). Inactive ingredients: excipients (61%)
PolyGuard™ is appropriate for treating a variety of bacterial, fungal, and parasitic diseases of exotic fish. Below are some of the more common diseases treatable with PolyGuard™. Be aware that many diseases and infections share similar physical and behavioral symptoms, e.g. clamped fins, lesions, loss of appetite.

Bacterial infection
Fins appear shredded, frayed, or decaying. Fin Rot is frequently mistaken for damage from fin-nipping fish. Contrary to the name, this is actually caused by bacteria, not fungus.
Suggested Treatment Period:
7 days or until infection clears
Special Considerations
Fin Rot is often found as a secondary infection (that’s an infection that started because the fish was already sick). Make sure to check for additional infections.
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