Fish Pen Penicillin 500mg Fish Antibiotic – 30 & 60 Tablets

Fish Pen Penicillin 500mg is a powerful, bactericidal fish antibiotic formulated to fight common bacterial infections in freshwater and saltwater aquarium fish. Each tablet contains 500mg of penicillin V potassium, an established beta-lactam antibiotic with strong activity against susceptible gram-positive and certain gram-negative bacteria.

Also commonly searched as Fish Pen Forte, this aquarium antibiotic is used to treat fin rot, tail rot, columnaris, Flexibacter infections, bacterial gill disease, infected eyes, popeye, skin ulcers, open wounds and other susceptible bacterial fish diseases.

Fish Pen attacks bacterial infections by blocking construction of the bacterial cell wall. Without a strong protective wall, susceptible bacteria rupture and die, helping stop the infection before it spreads or causes extensive tissue damage.

What Does Fish Pen Treat?

Fish Pen is designed for bacterial diseases caused by organisms susceptible to penicillin. It is especially useful for infections involving the fins, tail, skin, eyes, mouth and gills.

• Fin rot and tail rot
• Columnaris and Flexibacter infections
• Bacterial gill disease
• Infected eyes and bacterial popeye
• Bacterial mouth infections and mouth rot
• Open sores and skin ulcerations
• Infected cuts, wounds and abrasions
• Red lesions and inflamed tissue
• Bacterial skin and soft-tissue infections
• Secondary bacterial infections following injury or stress

Common Signs of a Bacterial Fish Infection

Bacterial infections can spread quickly and permanently damage the fish’s fins, eyes, skin and gills. Fish Pen may be appropriate when fish display symptoms consistent with an infection caused by susceptible bacteria, including:

• Frayed, deteriorating or discolored fins
• Receding tail tissue or inflamed fin edges
• Cloudy, swollen or protruding eyes
• Redness or inflammation around the eyes
• White, gray or damaged tissue around the mouth
• Open wounds, ulcers or crater-like sores
• Red patches, lesions or streaks on the body
• Pale, swollen or inflamed gills
• Rapid breathing or gasping near the surface
• Loss of appetite, weakness or unusual inactivity
• Fish hiding, isolating or remaining near the aquarium floor

Powerful Penicillin Antibiotic for Aquarium Fish

Penicillin V potassium belongs to the beta-lactam class of antibiotics. It binds to essential bacterial proteins and prevents susceptible bacteria from completing the construction of their protective cell wall.

As the damaged cell wall becomes unstable, the bacteria rupture and die. This bactericidal action makes Fish Pen a powerful treatment for susceptible bacterial infections involving the fins, tail, skin, eyes, mouth, gills and soft tissues.

Fish Pen provides its strongest activity against susceptible gram-positive bacteria while also affecting certain gram-negative organisms.

Why Fish Pen Is a Powerful Fish Antibiotic

• Contains 500mg of penicillin V potassium per tablet
• Provides powerful bactericidal antibacterial action
• Destroys susceptible bacteria by attacking the cell wall
• Strong activity against many gram-positive bacteria
• Treats fin rot, tail rot and bacterial fin infections
• Helps control columnaris and Flexibacter infections
• Useful for infected eyes and bacterial popeye
• Treats ulcers, wounds and bacterial skin infections
• Suitable for ornamental freshwater and saltwater fish
• Available in 30-tablet and 60-tablet packages

Available Fish Pen Sizes

Fish Pen 500mg – 30 Tablets

Fish Pen 500mg with 30 tablets provides a convenient supply of penicillin V potassium for aquarium owners requiring a powerful antibacterial fish treatment. Every tablet contains a consistent 500mg strength.

Fish Pen 500mg – 60 Tablets

Fish Pen 500mg with 60 tablets provides a larger supply for additional treatment requirements, larger aquarium systems or fish keepers maintaining several freshwater or saltwater aquariums.

Fish Pen for Fin Rot and Tail Rot

Fin rot and tail rot cause progressive deterioration of the fish’s fins. The tissue may become frayed, discolored, inflamed and increasingly shorter as the bacterial infection advances.

When the condition is caused by bacteria susceptible to penicillin, Fish Pen destroys the bacteria responsible for the infection and helps stop further loss of healthy fin and tail tissue.

Water quality must also be corrected because ammonia, nitrite, organic waste, overcrowding and chronic stress can weaken the fish and allow fin rot to return.

Fish Pen for Columnaris and Flexibacter

Columnaris, historically associated with the name Flexibacter, is a potentially aggressive bacterial disease affecting the mouth, skin, fins and gills. Signs may include white or gray patches, cotton-like mouth damage, saddle-shaped lesions, frayed fins and respiratory distress.

Fish Pen may be used when the infection is caused by a bacterial strain susceptible to penicillin. Early treatment is important because advanced columnaris can rapidly damage the skin and gill tissue.

Fish Pen for Infected Eyes and Popeye

Bacterial eye infections may cause cloudiness, swelling, inflammation and protrusion of one or both eyes. These symptoms may develop following an injury or as part of a wider systemic infection.

Fish Pen attacks susceptible bacteria involved in infected eyes and bacterial popeye. Excellent water quality should be maintained throughout treatment because ammonia, physical injury and environmental stress can also contribute to eye problems.

Fish Pen for Ulcers and Infected Wounds

Open wounds and skin ulcers provide a direct route for harmful bacteria to invade deeper tissues. Without effective treatment, a localized wound can develop into a severe soft-tissue or systemic infection.

Fish Pen provides bactericidal activity against susceptible bacteria involved in infected wounds, skin ulcers, red sores, lesions and damaged tissue.

Fish Pen for Bacterial Gill Disease

Bacterial gill disease damages the delicate respiratory tissue used by fish to absorb oxygen. Affected fish may breathe rapidly, remain near the surface, rub against aquarium objects or develop pale, swollen and inflamed gills.

Fish Pen may treat gill disease caused by bacteria susceptible to penicillin. Strong aeration and excellent water quality are essential while treating fish experiencing respiratory distress.

Freshwater and Saltwater Fish Antibiotic

Fish Pen may be incorporated into treatment programs for susceptible bacterial infections affecting ornamental fish maintained in freshwater and saltwater aquariums. This includes tropical fish, bettas, goldfish, koi, cichlids and marine ornamental species.

Whenever practical, move infected fish to a dedicated hospital or quarantine aquarium. A separate treatment environment makes it easier to monitor the fish, control medication use and protect healthy aquarium inhabitants.

Important Treatment Information

Confirm that the condition is bacterial before using Fish Pen. Penicillin treats susceptible bacterial infections; it does not eliminate parasites, viruses or true fungal diseases.

Follow the directions supplied with the product. Remove activated carbon, chemical filtration and UV sterilization when directed because these systems may reduce the available medication. Maintain strong aeration and monitor ammonia, nitrite, pH and fish behavior throughout treatment.

Complete the recommended treatment course even when symptoms begin improving. Ending antibiotic treatment too early may allow surviving bacteria to multiply, cause the infection to return and contribute to antibiotic resistance.

Product Details

• Product name: Fish Pen
• Also searched as: Fish Pen Forte
• Active ingredient: Penicillin V potassium
• Medication class: Beta-lactam penicillin antibiotic
• Product type: Bactericidal fish antibiotic
• Strength: 500mg per tablet
• Available quantities: 30 and 60 tablets
• Dosage form: Tablets
• Target: Susceptible bacterial infections
• Aquarium type: Freshwater and saltwater
• Intended use: Ornamental aquarium fish

Storage

Store Fish Pen in its original, tightly closed container in a cool, dry location. Protect the tablets from moisture, excessive heat and direct sunlight. Keep out of reach of children and animals.

Frequently Asked Questions

Is Fish Pen an antibiotic?

Yes. Fish Pen contains penicillin V potassium, a bactericidal beta-lactam antibiotic used against susceptible bacterial infections in ornamental aquarium fish.

What infections does Fish Pen treat?

Fish Pen is commonly used for fin rot, tail rot, columnaris, Flexibacter infections, bacterial gill disease, infected eyes, bacterial popeye, ulcers, wounds and other infections caused by bacteria susceptible to penicillin.

What is the active ingredient in Fish Pen?

Each Fish Pen tablet contains 500mg of penicillin V potassium.

How does Fish Pen work?

Penicillin blocks construction of the bacterial cell wall. Susceptible bacteria become structurally unstable, rupture and die.

Can Fish Pen treat fin rot and tail rot?

Fish Pen may treat fin and tail rot caused by bacteria susceptible to penicillin. Water quality, injuries and environmental stress should also be corrected.

Can Fish Pen treat columnaris?

Fish Pen may be used when columnaris is caused by a susceptible bacterial strain. Columnaris can progress rapidly, making early identification and treatment important.

Can Fish Pen treat popeye?

Fish Pen may help when popeye is associated with a susceptible bacterial infection. Popeye caused solely by physical injury or poor water quality requires correction of the underlying cause.

Can Fish Pen be used for freshwater and saltwater fish?

Fish Pen may be used in appropriate treatment programs for ornamental freshwater and saltwater fish according to the supplied directions.

Does Fish Pen treat parasites or fungal infections?

No. Penicillin is an antibacterial medication. It does not eliminate parasites, viruses or true fungal infections.

What sizes are available?

Fish Pen is available as 500mg tablets with either 30 or 60 tablets per package.

For ornamental fish use only. Not for human use or for fish intended for human consumption.