# Fritz Maracyn Two

**Brand:** Fritz
**Category:** Animals & Pet Supplies > Pet Supplies > Pet Medicine
**Taxonomy ID:** ap-2-34
**Google Category ID:** 5086
**Price:** $15.99
**Price Segment:** budget
**In Stock:** Yes

## Description

Treats bacterial infections (effective against gram-negative pathogens) Safe for aquarium plants Safe for shrimp, snails, and other invertebrates Fritz Maracyn® Two powder is a broad-spectrum antibiotic developed for use in aquariums which has been shown to be effective against a number of pathogenic bacteria associated with ornamental fish disease. Due to its unique properties, it is absorbed by the fish through the skin. During the prescribed treatment, the concentration of the active ingredient in the fish fluids rises to a therapeutic level and is available to fight systemic infections susceptible to its action. Maracyn® Two is primarily effective against gram-negative pathogenic organisms. Internal diseases are more difficult to detect than external ones as early detection is almost impossible. It is also potentially effective against some gram-positive and fungal infections, making it our most broad-spectrum treatment, and a great first choice of medication when the cause of disease is unknown. Provides relief from bacterial infections such as fin and tail rot, popeye, septicemia, dropsy, internal infections, and other secondary infections, such as wounds from injuries or parasites. Symptoms of possible bacterial infection can include clamped fins, general listlessness, degradation of tissue on fins, suppressed appetite or other unusual behavior can be caused by internal infections. All suspected bacterial infections should be treated immediately. Consult a veterinarian or fish expert for assistance in diagnosis of disease causing organisms and treatment options. Active ingredient: Minocycline For the 10-count and 20-count boxes of Maracyn Two, the medication comes in individual packets where each packet treats 10 gallons of water ( except for the first dose - see directions ). When treating with Maracyn Two, we recommend using an air stone in the aquarium, which may temporarily cause excessive foaming at the water surface. For best results, we recommend removing chemical filtration from your aquarium filter before dosing the medication. Examples of chemical filtration include activated carbon, carbon-infused media pads, Seachem Purigen, phosphate media pads, and ammonia media pads. Manufacturer's Directions on the Package: One complete course of treatment will take 5 days. Treat for the full course of treatment even if visible signs of infection or illness disappear. — Day One: Add the contents of two packets per 10 gallons of water to be treated. — Day Two through Day Five: Each day, add contents of one packet per 10 gallons of water to be treated. — Day Six: Perform a 25% water change. Repeat this five-day treatment if symptoms improve, but have not completely disappeared. If no improvement has occurred, try Maracyn. Aquarium Co-Op Instructions: We recommend following the manufacturers directions. Notes: — All suspected bacterial infections should be treated immediately. — Fritz Maracyn® Two is non-toxic to invertebrates such as snails and shrimp. — Don't confuse this medication with Maracyn, which is not the same medication.

## Specifications

### Ingredients & Nutrition

| Specification | Value |
|---|---|
| Key Ingredients | Minocycline |

### Performance

| Specification | Value |
|---|---|
| Benefits | Treats bacterial infections, effective against gram-negative pathogens, fights systemic infections |
| Skin Concern | fin and tail rot, popeye, septicemia, dropsy, internal infections, secondary infections, wounds |
| Target Species | Ornamental fish |
| Safety | Safe for aquarium plants, safe for shrimp, snails, and other invertebrates |

### Features & Construction

| Specification | Value |
|---|---|
| Product Form | Powder |
| Dosage | Each packet treats 10 gallons of water |

## Variants

| Variant | Price | Available |
|---|---|---|
| 10 count | $15.99 | Yes |
| 20 count | $21.99 | Yes |

## Frequently Asked Questions

**Q: Is Fritz Maracyn Two worth the price?**
A: Yes, Fritz Maracyn Two is a budget-friendly option priced at $15.99 for the 10-count box. It is a highly effective broad-spectrum antibiotic developed for ornamental fish, capable of treating internal and systemic bacterial infections that are often difficult to detect and treat using other standard medications.

**Q: What are the key ingredients in Fritz Maracyn Two?**
A: The active ingredient in Fritz Maracyn Two is Minocycline. This powder-form medication is a broad-spectrum antibiotic that is absorbed by fish through the skin, allowing the active ingredient to reach therapeutic levels in fish fluids to fight off systemic infections susceptible to its action.

**Q: Is Fritz Maracyn Two safe for shrimp and snails?**
A: Yes, Fritz Maracyn Two is safe for invertebrates including shrimp, snails, and aquarium plants. You can safely use this broad-spectrum antibiotic in your tank without worrying about harming these specific inhabitants, provided you follow the manufacturer's dosing directions for the full five-day treatment course.

**Q: How do you use Fritz Maracyn Two?**
A: On day one, add two packets per 10 gallons of water. From day two through day five, add one packet per 10 gallons daily. On day six, perform a 25% water change. For best results, remove all chemical filtration like activated carbon or Purigen before starting treatment.

**Q: What infections does Fritz Maracyn Two treat?**
A: Fritz Maracyn Two treats bacterial infections including fin and tail rot, popeye, septicemia, dropsy, and internal infections. It is primarily effective against gram-negative pathogens but may also be effective against some gram-positive and fungal infections, making it an excellent first-choice medication when the specific cause of fish disease is unknown.

**Q: Does Fritz Maracyn Two treat gram-positive or gram-negative bacteria?**
A: Fritz Maracyn Two is primarily effective against gram-negative pathogenic organisms. However, it is also potentially effective against some gram-positive and fungal infections. This versatility makes it a broad-spectrum treatment, providing relief from various secondary infections, including those resulting from injuries or parasites in your aquarium fish.

**Q: What is the difference between Fritz Maracyn Two and Maracyn?**
A: Fritz Maracyn Two and Maracyn are not the same medication and contain different active ingredients. Maracyn Two specifically uses Minocycline to treat gram-negative infections, while other formulations may target different bacteria. Always ensure you are using the correct medication for your suspected fish illness or consult a veterinarian for assistance.

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Data verified March 2026.

Source: https://aquariumcoop.com/products/fritz-maracyn-two