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SEACHEM Focus 5g

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  • Antibacterial, antifungal medicine
  • Heals fish internal infection
  • Can use alone or mixed with other medications or food
  • Freshwater or marine use

Seachem Focus is a fish medicine for fish internal infections, bacterial, fungal attacks. Mixed with food, it heals and nurses fish back to healthy state.

Seachem Focus can be used alone or mixed with food and/or other medications to make them palatable to fish and thereby reduces the loss of medication to the water through diffusion.

Seachem Focus is suitable for freshwater or marine aquarium.

Active ingredients: Active ingredient: polymer bound nitrofurantoin (0.1%)

Reasons for Medicated Food Mix

These are some of the reasons why we recommend dispensing Seachem Focus mix in food:

  • Your fish has an internal infection.
  • Bloating, abnormal stools, loss of appetite, and weight loss are all signs of a potential internal infection.
  • You are already treating with a medication in the water.
  • Sometimes fish will develop several infections at the same time, requiring multiple medications.
  • We do not recommend dosing two medications into the water, but it is possible to put one medication in the food and the other in the water.
  • There are corals, plants, or invertebrates in the tank.
  • Using a medicated food mix will prevent damage to delicate plants or invertebrates from medication.


Seachem Focus is appropriate for treating a variety of internal infections of fish. Below are some of the more common diseases treatable with Seachem Focus as part of a medicated food mix. Be aware that many diseases and infections share similar physical and behavioral symptoms, e.g. clamped fins, lesions, loss of appetite.


Eyes protrude or appear to be popping out of the head. Popeye is caused by a buildup of fluid behind the eye and is often seen in conjunction with Dropsy.

Suggested Treatment Period: KanaPlex blend: 1 week

Ich (White Spot)

  • Ichthyophthirius (freshwater) / Cryptocaryon (saltwater): Looks like salt sprinkled on the fishs body and fins. Usually accompanied by twitching, flashing, and other signs of stress and irritation. Several parasites are grouped under this name, but the symptoms are almost identical. Ich is among the most common infections of fish, and is entirely treatable with diligence and attention to water quality.
  • Suggested Treatment Period: MetroPlex blend: 14-21 days
  • Special Considerations: It is very important with this parasite to maintain the copper concentration for the full treatment period. A drop in the copper concentration will allow the parasite to multiply and reinfect the fish. Due to the nature of this parasite, it is normal for the visible signs of infection to get worse before they get better. The medication is still working, but it takes some time for the salt-like cysts on the fish to clear out. Keep up the treatment and the visible spots should clear soon!

Hole in the Head / Head and Lateral Line Erosion

  • Hexamita spp / Spironucleus vortens: Symptoms include a loss of color, erosion or lesions on the face, head, and body, and stringy white feces. This condition is often caused by an internal parasite, but factors like poor diet, poor water quality, and lack of trace elements will all contribute to this issue.
  • Suggested Treatment Period: MetroPlex blend: 14-21 days
  • Special Considerations: In freshwater this condition is called Hole in the Head. Research your fish preferred diet and water chemistry to ensure they are being properly duplicated in the aquarium. Consider using a nutrient soak for the food to provide essential vitamins and nutrients to the fish. In saltwater this condition is called Marine Head and Lateral Line Erosion. It can be caused by an internal parasite, but more often these symptoms are connected to nutrient deficiencies or poor water quality. Duplication of the natural environment, proper filtration, and a nutrient-rich diet are all essential to curing this condition in saltwater.

Hemorrhagic Septicemia

  • Aeromonas hydrophilia: Reddish streaks in the fins near the body or under scales. Common in goldfish. Associated with overcrowding and stress, particularly in goldfish and koi. It can also be caused by a virus.
  • Suggested Treatment Period: KanaPlex Blend: 1 week or SulfaPlex Blend: 3 weeks
  • Special Considerations: This infection is strongly linked to crowding and poor water conditions. Make sure your fish have clean water and plenty of space.


  • Symptom of internal damage: Fish appears bloated, scales stick out in a pinecone-like manner. Dropsy is a result of damage to the liver, causing fluid to build up in the fish. It often starts as bloat and progresses to Dropsy over time.
  • Suggested Treatment Period: KanaPlex blend: 1 week
  • Special Considerations: Dropsy is a sign of severe internal damage, not a symptom of a specific disease. It is treatable with KanaPlex if caught early, but sometimes the damage is too severe to respond to medications. The best defence is to catch internal infections early, before they progress to this stage.

Mouth Rot

  • Columnaris: Damaged fins, ulcers and yellowish patches on gills, tissue on head and mouth eaten away. This infection appears gruesome, but is entirely treatable. It is common to see fungus-like tufts around the face and mouth in addition to deterioration of tissue. It is essential to catch this disease early to prevent long-term damage.
  • Suggested Treatment Period: KanaPlex Blend: 1 week
  • Special Considerations: Columnaris is very contagious. If possible, remove the infected fish to treat separately in a hospital tank.