Fritz Maracyn Two is a powerful board-spectrum antibiotic designed to treat bacterial antibiotic infections in both freshwater and saltwater aquariums. This trusted aquarium supply effectively combats negative bacteria, which cause infections such as fin and tail rot, popeye, septicemia, dropsy, and internal bacterial diseases. Unlike external treatments, Fritz Maracyn Two is absorbed through the fish’s skin, ensuring deep, systemic relief. It's a great first-choice treatment when the cause of illness is uncertain and can be safely used alongside other Fritz medications like Maracyn and Coppersafe.
Key Benefits
Effectively treats both internal and external bacterial infections.
Safe for use in freshwater and saltwater aquariums.
Absorbed through the skin for deep, systemic treatment.
Can be used alongside Coppersafe, Maracyn, and Maracyn Oxy.
Easy packet dosing system for accurate treatment
Suitable for use in quarantine tanks.
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INGREDIENTS ANALYSIS
Active Ingredient: Minocycline
Attributes & Specifications
Form
Powder
Aquarium Type
Freshwater and Saltwater
Targeted Bacteria
Effective against gram-negative bacteria; also works on some gram-positive and fungal infections
Safe for Invertebrates
Yes, but may cause slight yellowing in some plants
Foaming & Cloudiness
May cause temporary cloudiness; excessive foaming in protein skimmers
Usage with Other Treatments
Can be used with Coppersafe, Maracyn, or Maracyn Oxy
Water Change Requirement
25% water change after completing the 5-day treatment
safety & precautions
For aquarium use only - not for human consumption.
Keep out of reach of children and pets.
Remove carbon filtration due to treatment to maximize effectiveness.
Monitor fish for signs of stress and discontinue use if necessary.
Do not perform water changes during treatment unless ammonia/nitrite levels rise.
DIRECTIONS FOR USE
Day 1: Add 2 packets per 10 gallons of water
Day 2 - 5: Add one packet per 10 gallons each day
Day 6: Perform a 25% water change
NOTE: If symptoms persist but improve, repeat the 5-day treatment once, If no improvement is seen, consider using Maracyn or Maracy Oxy.
For best results, use in a quarantine tank, maintain proper aeration, and complete the full treatment course even if symptoms improve early.
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Frequently Asked Questions
What Does Maracyn 2 Treat?+
Maracyn Two is for gram-negative bacterial infections, to which the majority of aquarium fish become infected. Maracyn is for gram-positive bacterial infections. If you see some improvement with the Maracyn Two, I would suggest a second treatment. As far as the fungus goes, some bacterial infections look like fungus.
Is Maracyn the Same as Maracyn 2?+
Maracyn is effective against gram-positive bacteria, and Maracyn 2 is effective against mostly gram-negative bacteria. They may be used in combination. Their combined use will adversely affect the ratio of good bacteria in your aquarium, including nitrifying bacteria that remove ammonia and nitrite.
How Do You Use Maracyn 2?
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On day one, add two packets for every 10 gallons of water. On days two to five, add one packet for every 10 gallons of water. Repeat this treatment once a day for five days if necessary. Cloudiness should be expected while using Maracyn Two.
What is the Active Ingredient in Maracyn 2?+
MINOCYCLINE!
Does Maracyn 2 Help Dropsy?+
Maracyn-Two is a great product. It successfully cured dropsy in one of my goldfish exhibitions two years ago. Keep it on hand, ready for use, as you will have to act rapidly (if, in fact, it's dropsy). It works very well for fin rot, too, and I have used it a couple of three or four times for that purpose.
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