Seachem Focus – Antibacterial Polymer & Medicated-Food Binder

Turn any medication into a targeted, fish-safe meal.

Dosing medication into the water wastes most of it to diffusion — and can wreck a planted or reef tank.

Seachem Focus is an antibacterial polymer for internal infections that doubles as a binder: mix it with another medication and it makes the dose palatable and keeps it in the food instead of leaching into the water. Perfect when there are corals, plants, or invertebrates in the tank. For freshwater or marine aquaria.

Focus reflects the science-driven approach Seachem has taken since it was founded in 1979 in Madison, Georgia. As a chemistry-led company whose products are developed and manufactured in-house by chemists and backed by research, Seachem engineered Focus as a polymer that binds medication into food and keeps it there — a filter-safe delivery method that spares the water column, and any residual medication is easily removed with activated carbon.

1. Identify the right medication for your fish's symptoms.
2. Mix 1 scoop of that medication + 1 scoop Focus + 1 tbsp food.
3. Feed once daily (about a minute's worth) for at least a week.

Deliver medicine where it works. Add to cart.

Why Seachem Focus

• Binds medication into food: keeps the dose in the food and palatable instead of leaching into the water, so far more of it reaches the fish.
• Protects delicate tanks and the biofilter: because it targets the food rather than the water column, it spares corals, plants, invertebrates, and your biological filtration.
• Easily removed with carbon: any residual medication in the water can be lifted with activated carbon after treatment.
• Seachem polymer chemistry: a research-backed antibacterial polymer (polymer-bound nitrofurantoin) designed to pair with other Seachem medications.

Best For

Use Focus in freshwater or marine aquaria when your fish has an internal infection (bloating, abnormal stools, loss of appetite, weight loss), when you're already treating another infection in the water, or when there are corals, plants, or invertebrates you need to protect. It is a binder, so combine it with a medication chosen for the disease — MetroPlex, KanaPlex, SulfaPlex, or NeoPlex — and deliver the treatment through food rather than the water column.

When to Use a Medicated Food Mix

Your fish has an internal infection (bloating, abnormal stools, loss of appetite, weight loss); you're already treating another infection in the water; or there are corals, plants, or invertebrates you need to protect.

Directions

Focus should be combined with another medication chosen for your fish's disease. Stir together the mix and feed once daily, as much as fish eat in about 1 minute; treat for at least a week. Refrigerate or freeze between feedings.

Food mix: 1 scoop of chosen medication + 1 scoop Focus + 1 tbsp food (pellets or frozen) + a few drops of water if using dry food. Use with GarlicGuard to enhance palatability.

Pairs with: MetroPlex (internal/external parasites & bacteria), KanaPlex (bacterial & fungal), SulfaPlex (external fungal & bacterial), NeoPlex (intestinal bacterial).

Active Ingredient

Polymer-bound nitrofurantoin (0.1%).

Available Sizes

5 g, 100 g

FAQ

Is Focus safe for invertebrates and reef tanks? Yes — that is exactly what it's for. By binding medication into food, Focus lets you treat internal infections without dosing the water column, protecting corals, plants, and invertebrates.

How do I remove Focus after treatment? Because it's delivered through food, little enters the water; any residual medication can be lifted with activated carbon after treatment.

Can I use Focus in food? Yes — it is designed for it. Mix 1 scoop of your chosen medication + 1 scoop Focus + 1 tbsp food (with a few drops of water for dry food) and feed once daily for at least a week. GarlicGuard can improve palatability.