The reef-safer answer to stubborn internal parasites.Protozoan parasites and internal infections are hard to treat without harming a planted or invertebrate tank.Seachem MetroPlex is a gentle, effective metronidazole treatment for protozoan and anaerobic bacterial diseases. It won't harm the biofilter, is easily removed with carbon, and can be dosed in water or bound to food with Focus to treat internal and external infections — with little danger of overdosing.MetroPlex is formulated with the science-driven chemistry Seachem has relied on since it was founded in 1979 in Madison, Georgia. As a company whose products are developed and manufactured in-house by chemists and backed by research, Seachem designed MetroPlex to be gentle and hard to overdose while remaining filter-safe — it won't harm your biological filtration — and easily removed with activated carbon after treatment. Remove invertebrates; turn off UV/ozone and remove carbon and Purigen. Dose 1–2 measures per 40 L (10 US gallons) every 48 hours. Or mix into food with Focus for internal infections in invertebrate tanks. Treat gently, even in delicate tanks. Add to cart.Why Seachem MetroPlex Gentle and hard to overdose: an effective metronidazole treatment with little danger of overdosing, so it's forgiving even in delicate setups. Filter-safe: won't harm the beneficial bacteria in your biological filtration during treatment. Easily removed with carbon: lift residual medication with activated carbon (MatrixCarbon) after treating. Concentrated Seachem chemistry: a research-backed metronidazole formula that can be dosed in water or bound into food with Focus to reach internal infections. Best ForUse MetroPlex in freshwater or marine aquaria to treat protozoan and anaerobic bacterial diseases including ich/white spot, velvet, and hole-in-the-head / head and lateral line erosion (HLLE). Its gentle nature makes it a strong choice when you need to treat internal infections in planted or invertebrate tanks — remove invertebrates before dosing in water, or bind MetroPlex to food with Focus to treat internal infections without medicating the whole invertebrate tank.What It TreatsProtozoan and anaerobic bacterial diseases including ich/white spot, velvet, and hole-in-the-head / head and lateral line erosion (HLLE).DirectionsDosing in water: Remove all invertebrates. Turn off UV and ozone filters and remove chemical filtration (MatrixCarbon, Purigen). Use 1–2 measures (included) per every 40 L (10 US gallons). Repeat every 48 hours for up to 3 weeks or until symptoms disappear.Dosing in food (feed daily until the infection clears, up to 3 weeks): 1 scoop MetroPlex + 1 scoop Focus + 1 tbsp food (pellets or frozen) + a few drops of water if using dry food. Use with GarlicGuard to enhance palatability.After treating: Remove with activated carbon (MatrixCarbon).Active IngredientsMetronidazole (70%). Inactive ingredients: excipients (30%).Available Sizes5 g, 100 gFAQIs MetroPlex safe for invertebrates? Remove all invertebrates before dosing in water. To treat internal infections in an invertebrate tank, bind MetroPlex to food with Focus instead of dosing the water column.How do I remove MetroPlex after treatment? Run activated carbon (MatrixCarbon) in your filter once the course is complete to lift residual medication.Can I use MetroPlex in food? Yes. Mix 1 scoop MetroPlex + 1 scoop Focus + 1 tbsp food (with a few drops of water for dry food) and feed daily until the infection clears, up to 3 weeks. GarlicGuard can improve palatability.