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Seachem | SulfaPlex

Seachem | SulfaPlex

Regular price $ 9.99 USD
Regular price $ 14.99 USD Sale price $ 9.99 USD
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SulfaPlex™ is an effective and safe treatment for many bacterial, fungal and protozoan infestations in the aquarium. While it can be used in both freshwater and saltwater, it is particularly effective against the common bacterial and fungal infections of freshwater fish. It is also among the gentler antibiotics, and great for treating fish that are already stressed. It is easily removed with carbon and does not impair nitrification.

Types of Infections Treated

Parasitic Fungal Bacterial Viral
SulfaPlex Seachem | Sulfaplex Seachem | Sulfaplex Seachem | Sulfaplex

Dosing in Water

Remove all invertebrates - these are extremely sensitive to medication. Turn off UV filters, ozone filters, and remove chemical filtration like MatrixCarbon™ and Purigen™. Use 2-3 measures (included) per every every 40 L (10 US gallons). Repeat this dose every 72 hours for a maximum of 3 weeks.

Dosing in Food

SulfaPlex™ is most effective when used in the water, but it can also be added to the food. Feed the medicated food mix (recipe below) every day until the infection clears or up to 3 weeks.

  • 1 scoop SulfaPlex™

  • 1 scoop Focus™

  • 1 tbsp food (preferably pellets or frozen food)

  • A few drops of water if using a dry food

To enhance palatability use with GarlicGuard™ or Entice™.

After Treating

When the treatment period is over, SulfaPlex™ can easily be removed using activated filter carbon like MatrixCarbon™. It does not linger in the substrate or filter media of the tank.

Active ingredients: sulfathiazole (69%). Inactive ingredients: excipients (31%)


5 g, 100 g

Treatable Diseases

Common Fish Diseases Treatable with SulfaPlex

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: 3 weeks or until infection clears

A quick note about bacterial and fungal infections! Most bacterial infections appear in conjunction with poor water quality or another infection (called a “primary infection”). Do a water test to ensure your water quality is still good and do water changes if necessary to improve your water quality before treating with a medication.

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