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The Beginner Guide To Saltwater Fish Medication And Treatment

Updated 2024

Disclaimer: Let me reiterate – I am NOT an expert, veterinarian, or medical professional. However, I have dedicated years to curating the most accurate information I could gather. The saltwater hobbyist community often finds consensus elusive, particularly regarding the identification and treatment of fish diseases. Therefore, I urge you to view this guide as an initial stepping stone for your research endeavors.

Navigating the realm of saltwater fish medication and treatment is undeniably one of the most intricate facets of this hobby, often inducing a sense of overwhelming complexity. A multitude of blogs and online communities delve into every conceivable detail of this subject. Yet, I found a void in the landscape – a lack of a comprehensive and easily digestible guide that unifies the entirety of this domain. This is precisely the purpose of this guide.

Why is this topic so challenging, you ask?

Regardless of your efforts, fish mortality can persist.
Oftentimes, by the time you detect an issue, it’s already too advanced.
Different species exhibit varying responses to specific medications.
Medications might inadvertently harm your beneficial bacteria and invertebrates.
In the absence of experience, you lack a baseline to discern normal from abnormal.
Numerous diseases exhibit similar symptoms, yet demand distinct treatments.

The underlying concept is clear.

Without question, your foremost strategies should encompass preemptive disease prevention and the implementation of a quarantine tank.

Take pleasure in perusing this guide, and feel free to reach out with suggestions or potential inaccuracies at contact@myfirstfishtank.com.

For an exhaustive exploration of fish diseases, I recommend referring to the book penned by Edward Noga below. It is widely acclaimed as the definitive compendium on fish diseases.

I) Common Treatments For Marine Fish Infections

The intention of this section is to provide a brief overview of each method. For more comprehensive instructions on how to execute each method, a straightforward Google search will undoubtedly provide the desired results! Additionally, there’s the possibility of another guide being crafted in the future.

If you wish to explore a particular section in more detail, feel free to click on the links provided below to directly access that section:

1. Freshwater Dip

Freshwater dips serve as a temporary measure to offer relief from parasites. The underlying concept revolves around the aversion external parasites have towards hyposalinity. When exposed to freshwater for a span of 3-5 minutes, these parasites are inclined to detach from the fish. Despite the process not being favored by the fish, they generally exhibit greater resilience than the parasites.

Here’s a succinct breakdown of the process:

  1. Fill a container with RODI or distilled water.
  2. Adjust the water temperature to match that of your display tank.
  3. Optionally, introduce an ammonia-neutralizing product like Kordon AmQuel and an antibiotic such as API Furan 2 to mitigate the risk of secondary infections.
  4. Gently place the fish into the container, ensuring the water remains in motion with the aid of a turkey baster.
  5. Should your fish display severe distress, promptly remove it from the dip.

It’s important to note that a freshwater dip doesn’t constitute a definitive solution for parasites; however, it can help eliminate certain parasites and extend the lifespan of your fish, allowing them more time to respond to anti-parasitic medications like Hikari PraziPro.

Nevertheless, if your fish is already grappling with disease-induced stress, subjecting it to a freshwater dip might exacerbate the situation and lead to its demise.

 

2. Tank Transfer Method

Let’s delve into the essence of the tank transfer method. It’s crucial to recognize that this method is primarily effective against Marine Ich. Consequently, correctly identifying the disease is paramount.

The Tank Transfer Method (TTM) operates by disrupting the lifecycle of the ich parasite. The fundamental idea is to relocate your fish between tanks every 72 hours. The strategy hinges on the probability that, during one of these transfers, the ich will detach from the fish but will not have had sufficient time to reproduce. Therefore, ensuring the thorough sterilization of each bucket or tank between transfers becomes essential, as this eradicates the ich present at the base of the container.

You’ll require either two buckets or two quarantine tanks equipped with separate apparatus. Alternatively, two sizable buckets can serve the purpose, provided you include hiding spots like PVC pipes, a thermometer, and an air stone.

This procedure unfolds over a span of 13 days, involving four fish transfers, each spaced exactly 72 hours apart (and no longer!). After each transfer, ensure you sterilize the bucket using either vinegar or bleach before replenishing it with fresh saltwater.

For a comprehensive walkthrough of this method, simply initiate a Google search by clicking HERE.

3. Hyposalinity

Distinguishable from a freshwater dip, the hyposalinity method involves a protracted quarantine procedure in which your fish resides within a low-salt environment designed to combat marine Ich.

Though debates exist, hyposalinity has demonstrated effectiveness against ich, and its efficacy against other parasite types is also under discussion.

In essence, the fish exhibits greater resilience to reduced salt levels compared to the parasite.

While comprehensive guides are readily available, here’s a basic overview:

– Only employ this method in a quarantine tank specifically designated for fish, avoiding its use in reef tanks or alongside other invertebrates.
– Over a 48-hour timeframe, gradually decrease the salinity of the quarantine tank until it reaches a specific gravity of 1.009.
– Commence a four-week countdown from the moment your fish becomes free of ich.
– If the ich resurfaces at any point, the countdown must reset.
– After an ich-free duration of four weeks, you can cautiously raise the salinity to the standard level, while keeping the fish in quarantine for an additional four weeks.

For more detailed insights, numerous comprehensive guides are accessible. To locate them, simply click HERE.

A UV sterilizer isn’t a miraculous panacea, but it does offer assistance in neutralizing free-floating algae, bacteria, and parasites.

Essentially, a UV sterilizer comprises a tubing housing a UV bulb. Water, propelled by a pump, enters and exits the sterilizer, encountering the UV light in the process. The UV light disrupts the DNA within cells, hindering their replication and ultimately causing their demise.

In the marine tank context, UV sterilizers are recognized for their effectiveness in diminishing and eliminating cyanobacteria, Marine Ich, Marine Velvet, and algae spores. However, it’s vital to reiterate that they solely target free-floating organisms. Consequently, they wield no influence whatsoever on parasites that have affixed themselves to your fish or that reside within the substrate.

A common misconception revolves around the notion that different species of cleaner shrimp can alleviate certain parasitic infections in fish by consuming them. However, research examining the stomach contents of cleaner shrimp has revealed that they, in fact, do not consume a substantial number of parasites.

Hence, the key takeaway here is that if your fish is grappling with any form of parasitic infection (such as ich, velvet, or flukes), resorting to a cleanup crew comprising cleaner shrimp is not a viable solution.

II) Saltwater Fish Medications

Alright, brace yourself for what might be the lengthiest and most intricate segment, catering to both newcomers and seasoned aquarists alike! Let’s delve into our approach…

Organized by categories (parasitic, bacterial, fungal), we will systematically explore the prevalent medications accessible and their respective applications. For viral conditions, we’ll bypass this aspect, as there are no specific medications.

Consequently, this section entails an in-depth analysis of medications. If you’re grappling with fish disease diagnosis, make sure to consult The Beginner Guide To Saltwater Fish Disease.

A quick reminder: Our intent is not to endorse any of the medications outlined below. Rather, we aim to provide assistance in comprehending this intricate domain.

Feel free to utilize the links below for swift navigation to your desired section.

Antiparasitics

Here’s a compiled list of medications, organized alphabetically according to the respective companies. Please note that this is not an exhaustive roster. The inclusion of a product here doesn’t signify our endorsement.

Before proceeding, familiarize yourself with a couple of terms:

– Biofilter Safe: Certain medications may harm the beneficial bacteria within your tank, potentially leading to ammonia and nitrate spikes. If a medication isn’t deemed biofilter safe, it should be confined to use within a quarantine tank devoid of live rock.
– Reef Safe: Specific medications might pose a threat to invertebrates (corals, anemones, snails, crabs, and the like). If a medication isn’t considered reef safe, its usage should be restricted to a quarantine tank without invertebrates.

1) API General Cure

      • Active Ingredient(s): Metronidazole (antibiotic) & Praziquantel (antiparasitic).
      • Details: Gram-negative plus a parasitic.
      • Biofilter Safe? Yes.
      • Reef Safe? Not reef safe unless used with the binding agent Seachem Focus, and food.
      • What It Treats: Gill & skin flukes, swollen abdomen, velvet, and hole-in-the-head disease.

2) Hikari Prazipro

      • Active Ingredient(s): Praziquantel.
      • Details: Anti-worm medication that prevents larvae from growing and multiplying.
      • Biofilter Safe? Yes.
      • Reef Safe? Yes.
      • What It Treats: Flukes, tapeworms, flatworms, and turbellarians.

3) Hikari Ich-X

      • Active Ingredient(s): A proprietary formula of water and formaldehyde (<3%)
      • Details: A low dose of formalin (<3%), so probably not a great treatment for Brooklynella.
      • Biofilter Safe? Relatively safe when used as directed.
      • Reef Safe? No.
      • What It Treats: Marine Ich, external protozoan, & fungal diseases.

4) Kordon Ich Attack

      • Active Ingredient(s): 100% natural organic herbals.
      • Details: An all natural ich treatment, questionable efficacy when compared to other chemical ich treatments.
      • Biofilter Safe? Yes.
      • Reef Safe? Yes.
      • What It Treats: Marine ich, protozoan, and fungal infections.

5) Mardel Coppersafe

      • Active Ingredient(s): Chelated Copper
      • Details: Relief from unwanted parasites.
      • Biofilter Safe? Unknown, but formalin is known to have a negative affect on the biofilter.
      • Reef Safe? No.
      • What It Treats: Marine ich (may be ineffective), protozoan parasites, and mild fluke outbreaks.

6) Polyplab Medic

      • Active Ingredient(s): Crystallized Peroxide Salts.
      • Details: Water conditioner used to de-pollute water. Contains reef safe oxidizing agent.
      • Biofilter Safe? Yes.
      • Reef Safe? Yes.
      • What It Treats: Marine ich, and possibly marine velvet

7) Ruby Reef Kick Ich Pro

      • Active Ingredient(s): 5-Nitroimidazoles
      • Details: Targets Marine Ich during its infectious, free swimming stage.
      • Biofilter Safe? Yes.
      • Reef Safe? Yes.
      • What It Treats: Marine ich.

8) Ruby Reef Rally Pro

      • Active Ingredient(s): Acriflavine, Aminoacridine, & Formalin.
      • Details: Copper free, reef safe treatment for marine fish with fin rot, flukes, & parasites.
      • Biofilter Safe? Yes.
      • Reef Safe? Yes.
      • What It Treats: Fin rot, flukes, marine velvet, & brooklynella.

9) Copper Power

      • Active Ingredient(s): Copper
      • Details: The gold standard for treating marine ich and velvet.
      • Biofilter Safe? No.
      • Reef Safe? No.
      • What It Treats: Marine ich & marine velvet.

10) Seachem Metroplex

      • Active Ingredient(s): Metronidazole.
      • Details: Gram-negative antibiotic.  Can use together with Seachem Kanaplex & Seachem Focus for a more broad spectrum.
      • Biofilter Safe? Yes.
      • Reef Safe? Only when used with the binding agent Seachem Focus. You don’t want Metroplex in the water column.
      • What It Treats: Marine ich (although most hobbyists disagree)& hole in the head.

11) Seachem Paraguard

      • Active Ingredient(s): Aldehydes, Malachite Green, & Polymers.
      • Details: Employs a proprietary, synergistic blend of aldehydes, malachite green, and fish protective polymers that effectively eradicates many ectoparasites and external fungal, bacterial, and viral lesions.
      • Biofilter Safe? Yes.
      • Reef Safe? No
      • What It Treats: Ectoparasites (ich, velvet), fin rot, flukes, external fungal & bacterial lesions.

Antibacterials

In order to grasp the rationale behind the multitude of antibiotics available, it’s essential to delve into the concept of Gram staining.

Gram Staining

Devised in 1882 by Danish bacteriologist Hans Christian Gram, the technique of Gram staining aids in discerning distinct bacterial types by assessing their affinity for a purple dye.

Bacteria that do readily absorb the dye are classified as Gram-positive, while those that do not are categorized as Gram-negative.

Given this backdrop, it’s understandable that diverse antibiotics exhibit varying efficacy against different bacterial infections (admittedly, it’s a complex realm!).

It’s worth noting that Gram-negative infections are prevalent in saltwater fish. However, it’s important to consider that many nitrifying bacteria also fall under the Gram-negative category. Consequently, employing a Gram-negative antibiotic might inadvertently damage or eliminate your biological filter.

Categories of Antibiotics

The majority of antibiotics can be categorized into three main groups:

1. Gram positive
2. Gram negative
3. Broad spectrum

Especially for beginners, opting for a broad spectrum antibiotic is typically advised, as it offers a higher likelihood of effectively treating a wide range of bacterial infections.

Common Antibiotic Medications

The subsequent medications are arranged alphabetically according to the respective company. However, please note that this list is not comprehensive. Inclusion here does not indicate our endorsement of the product.

1. API E.M. Erythromycin

      • Active Ingredient(s): Erythromycin.
      • Details: Broad spectrum, but more so Gram positive.
      • Biofilter Safe? Yes in moderation.
      • Reef Safe? Yes in moderation.
      • What It Treats: Fin/tail rot, open wounds, body fungus, gill disease, popeye & cyanobacteria.

2) API General Cure

      • Active Ingredient(s): Metronidazole (antibiotic) & Praziquantel (antiparasitic).
      • Details: Gram-negative plus a parasitic.
      • Biofilter Safe? Yes.
      • Reef Safe? Not reef safe unless used with the binding agent Seachem Focus, and food.
      • What It Treats: Gill & skin flukes, swollen abdomen, velvet, and hole-in-the-head disease.

3) API Melafix

      • Active Ingredient(s): Melaleuca. 
      • Details: All natural tea tree oil, broad spectrum, homeopathic. Can be combined with API Pimafix.
      • Biofilter Safe? Yes.
      • Reef Safe? Yes
      • What It Treats: Open wounds, abrasions, fin/tail rot, cloudy eye, mouth fungus, and promotes regrowth of damaged fins and tissues.

4) API Pimafix

      • Active Ingredient(s): Pimenta Racemosa. 
      • Details: Broad spectrum bay rum oil. Primarily an antifungal with minimal antibiotic properties.  Melafix is better for bacterial infections, but you can combine the two together.
      • Biofilter Safe? Yes.
      • Reef Safe? Yes
      • What It Treats: fungal infections on body and fins.

5) Fritz Maracyn

      • Active Ingredient(s): Erythromycin.
      • Details: Broad spectrum but more so Gram positive.
      • Biofilter Safe? Yes in moderation.
      • Reef Safe? Yes in moderation.
      • What It Treats: Fin/tail rot, open wounds, body fungus, gill disease, popeye & cyanobacteria.

6) Fritz Maracyn 2

      • Active Ingredient(s): Minocycline.
      • Details: Broad spectrum.
      • Biofilter Safe? Yes with caution.
      • Reef Safe? Yes, with caution.
      • What It Treats: Fin/tail rot, popeye, dropsy, internal & external infections.

8) Seachem Focus

      • Active Ingredient(s): Polymer bound nitrofurantoin.
      • Details: Acts as a binding agent & meant to be mixed with other medications and food to treat internal infections.
      • What It Treats: Depends on what antibiotics it is combined with.

9) Seachem Kanaplex

      • Active Ingredient(s): Kanamycin.
      • Details: Broad spectrum.
      • Biofilter Safe? Yes.
      • Reef Safe? Yes in moderation.
      • What It Treats: Fin/tail rot, dropsy, popeye. Can be combined with Seachem Metroplex & Seachem Focus

10) Seachem Metroplex

      • Active Ingredient(s): Metronidazole.
      • Details: Gram-negative antibiotic.  Can use together with Seachem Kanaplex & Seachem Focus for a more broad spectrum.
      • Biofilter Safe? Yes.
      • Reef Safe? Only when used with the binding agent Seachem Focus. You don’t want Metro in the water column.
      • What It Treats: Marine ich (although most hobbyists disagree)& hole in the head.

11) Seachem Neoplex

      • Active Ingredient(s): Neomycin Sulfate.
      • Details: Broad spectrum.
      • Biofilter Safe? Yes with caution.
      • Reef Safe? With caution. Tolerated by most invertebrates, although may stress delicate species.
      • What It Treats: Most external infections such as fin/tail rot, bacterial lesions, bloat, & mouth rot.

Antifungals

The medications listed below are organized alphabetically by company. Please be aware that this list is not comprehensive. Additionally, its presence here does not indicate our endorsement of the product.

1) API Melafix

      • Active Ingredient(s): Melaleuca. 
      • Details: All natural tea tree oil, broad spectrum, homeopathic. Can be combined with API Pimafix.
      • Biofilter Safe? Yes.
      • Reef Safe? Yes
      • What It Treats: Open wounds, abrasions, fin/tail rot, cloudy eye, mouth fungus, and promotes regrowth of damaged fins and tissues.

2) API Pimafix

      • Active Ingredient(s): Pimenta Racemosa. 
      • Details: Broad spectrum bay rum oil. Primarily an antifungal with minimal antibiotic properties.  Melafix is better for bacterial infections.  Can be combined with API Melafix.
      • Biofilter Safe? Yes.
      • Reef Safe? Yes
      • What It Treats: Fungal infections on body and fins.

3) Kordon Malachite Green

      • Active Ingredient(s): Chloride salt
      • Details: More harsh than Kordon Methylene Blue. Often combined with formalin.
      • Biofilter Safe? Yes, when concentrations don’t exceed 0.1 ppm.
      • Reef Safe? No
      • What It Treats: Marine ich, velvet, & fungal infections.

4) Kordon Methylene Blue

      • Active Ingredient(s): Chloride salt.
      • Details: Better tolerated than Kordon Malachite Green.
      • Biofilter Safe? No.
      • Reef Safe? No.
      • What It Treats: Various fungal infections.