Treatment Options 102
The purpose of this article is to provide information on available options for treating diseases afflicting saltwater fish. Every treatment discussed will contain the following information: “What It Treats”, “How To Treat”, “Pros”, and “Cons/Side Effects”. Each treatment is listed alphabetically.
Before we begin, below are some things I’ve discovered that seem to apply no matter what medication you use:
- There are almost no “reef safe” medications that will actually eradicate diseases. A couple of notable exceptions are Prazipro and soaking fish food with metronidazole. There are several “reef safe” herbal remedies but those are designed to manage symptoms.
- Do not mix or overdose medications. You can use antibiotics in conjunction with most anti-parasitic meds, but do so only as a last resort.
- Do not use ammonia reducers, such as Amquel or Prime, in conjunction with any medication (especially copper).
- Discontinue use of UV, ozone, dosing, protein skimmer and chemical filtration (ex. carbon) while using medications. However, you can use activated carbon (or a poly filter) to remove medication when you wish to end treatment.
- Most medications will not deplete a bio-filter to the point where it no longer works. The bio-filter will continue to break down ammonia even after being exposed to medication.
- Almost all medications deplete oxygen, so be sure to increase gas exchange while using them. I think failure to do this has led to many fish deaths. Adding an air stone and/or pointing a powerhead towards the surface of the water is a good idea when using medications.
- Almost all medications render liquid ammonia test kits useless. You have to use a Seachem “Ammonia Alert” badge:
Simply put, medicating fish can be a challenge. Following the tips above and information below will increase your chances of success, but understand that every fish is unique and has different tolerances. So, a Flame Angel you are currently treating with copper may experience difficulties even though your last one did just fine in the same medication. Live animals with various quirks are the “X factors” we are always dealing with in this hobby. Anyway, onto the list…
Acriflavine: I have no first-hand experience with this medication, so everything I know about it comes from one LFS (treating Brooklynella), Google Scholar or other literature. It supposedly is effective against protozoans, bacterial infections and external fungal diseases; however Brook & Uronema are the only two I would bank on. It also is supposedly “reef safe”, so long as it is not mixed with any other medication (very important!)
How To Treat - Follow the directions on the label of whatever product you are using. Acriflavine is often mixed with other medications; however Acriflavine-MS is the pure form (and most likely to be “reef safe.”)
Pros - Alternative treatment for Brooklynella & Uronema (useful in locales where formalin is banned); possibly “reef safe.”
Cons/Side Effects - Acriflavine is a “new” medication (to me), so it’s full range of effect is not completely understood. Same goes for possible side effects.
Antibiotics: Treats bacterial infections, which are oftentimes “secondary” to preexisting parasitic infestations.
How To Treat - Follow the directions on the label of whatever product you are using. Always use a broad spectrum antibiotic medication i.e. one that treats both gram-positive and gram-negative bacterial diseases (very important). Examples of this include Furan-2, Kanamycin aka Seachem Kanaplex, Nitrofuracin Green Powder, Triple Sulfa Powder or a combination of using both Erythromycin & Minocycline. The latter can be accomplished (albeit expensively) by using freshwater Maracyn 1 & 2 and then doubling the dosage for saltwater use. When battling a particularly nasty bacterial infection, combining Furan-2, Kanaplex and metronidazole (ex. Seachem MetroPlex) can be very effective (and safe). Props to “hedgedrew” for enlightening me of this.
Normally you have to do 4 doses to complete a full course of treatment. The instructions may say to dose every 24 hours, and perform water changes at certain intervals. In my experience, you often have to do 2 full courses of treatment (or 8 doses total) before a fish will show signs of improvement (antibiotics are notoriously slow acting with fish). If a fish shows no signs of improvement after the second full course, then it’s time to try a completely different medication. Just like with humans, sometimes a certain fish will respond better to a different antibiotic. You can run activated carbon at any time when you wish to end treatment.
Pros - One of the few medications that can safely be mixed with others. You can use antibiotics in conjunction with just about everything.
Cons/Side Effects - Appetite suppression, depletes the water of oxygen (so provide additional gas exchange).
Chloroquine phosphate: Treats Ich (Cryptocaryon irritans), Marine Velvet disease (Amyloodinium), Brooklynella hostilis & Uronema marinum.
How To Treat - Chloroquine phosphate (CP) is a “new drug” that actually was widely used to control external protozoa in saltwater aquariums back in the 70s & 80s. It was even used in some aquarium medications sold at LFS. Nowadays CP requires a prescription to purchase legitimately, making it more difficult to obtain. Fast forward to today and thanks to the power of the Internet, CP has come roaring back! The biggest obstacle to overcome is obtaining pharmaceutical grade 99% pure CP. I cannot stress the importance of this enough. Do not buy it from some guy on eBay or even an online vendor. The only way to be sure you are getting 99% pure CP is to get your vet to write you a prescription that can then be filled at a local pharmacy.
CP is a “one and done” medication, meaning you dose once and that’s it. There are no test kits for CP, so it’s important that you dose accurately using a digital scale. Also, don’t forget to dose any replacement water (from water changes, but not top off) with CP. The dosage rates are as follows:
- Prophylactic treatment is 40 mg per gallon.
- Active infections (visible symptoms present) is 60mg/gal.
- For Uronema marinum and really bad infestations, you can dose up to 80mg/gal.
Pros - Gentle on most fish (DO NOT USE with wrasses), a “one and done” medication that treats most external protozoa. CP is the closest thing there is to a “wonder drug” in our hobby.
Cons/Side Effects - Expensive, hard to get (requires a prescription), light sensitive; some evidence of appetite suppression with certain species (especially wrasses.) Attempts to feed CP laced food are usually not successful due to its bad metallic taste.
Copper: Treats Ich (Cryptocaryon irritans), Marine Velvet disease (Amyloodinium); possibly Uronema marinum
How To Treat - First, it is important to know what kind of copper you are using. Cupramine is fully charged (ionic) copper, and has a therapeutic range of 0.35-0.5 mg/L or ppm. You would use a Seachem or Salifert copper test kit for Cupramine, as those are capable of reading copper in the low range. Coppersafe, on the other hand, is chelated copper. It has a much higher therapeutic range of 1.5-2.0 mg/L or ppm. As such, you need a “total copper test kit” such as API’s to measure Coppersafe.
Standard copper treatment lasts 30 consecutive days. The reason it takes so long is copper only targets the “free swimming stage” (the same holds true for all chemical treatments & hypo). While 7-14 days is the “norm” to reach this stage, certain strains of ich have prolonged life cycles. Indeed, even 30 days may not be long enough in some rare cases. This is why it is so important to observe after treatment ends, to ensure symptoms do not return.
Therapeutic copper levels must be maintained at all times during the 30 days, so testing often is important. If the level drops even slightly out of range, then the 30 day clock starts all over again. One reason your copper level may drop unexpectedly is if you are treating in a tank with rock and substrate; those should not be used in the presence of copper due to absorption. Conversely, if you exceed the therapeutic range you risk killing the fish.
Copper is a poison, pure and simple. It only works because most fish are able to withstand being in it longer than the parasites. Knowing this, it is wise to raise your copper level very slowly (over 3-5 days) instead of the usual 24-48 hours recommended on the labels. Doing so increases your odds of successfully treating a “copper sensitive” fish. Remove copper after 30 days by running activated carbon.
Pros - Readily available
Cons/Side Effects - Appetite suppression is a common side effect. If a fish stops eating, don’t add more copper until he resumes. If the fish is still not eating after 2-3 days, start doing water changes (lowering the copper concentration) until he eats. If this happens a second time after you resume raising the copper, you’ll know you’ve encountered a “copper sensitive” fish and an alternative treatment should be used instead. Some species of fish, such as angels, puffers, lions and mandarins are notoriously difficult to treat with copper.
Dimilin: Treats anchor worms. Note: Worms still need to be removed from the fish by using tweezers before beginning treatment.
How To Treat - Follow instructions on the label of whatever product you are using (just be sure it lists dimilin or diflubenzuron as an active ingredient). Anchor worms are mostly seen in Koi, so any place selling pond supplies might carry dimilin. It is also sometimes sold on Amazon & eBay (or they’ll have an alternative). For example, I searched for “dimilin” on Amazon and Microbe-Lift Lice and Anchor Worm Treatment came up, a suitable alternative. For quarantine use only.
Pros - Safe & effective.
Cons/Side Effects - NOT reef safe.
Epsom Salt: Treats eye and other injuries. Popeye in one eye usually means injury, but popeye in both eyes usually denotes a bacterial infection requiring antibiotic treatment. Cloudy eye can be a bacterial infection or flukes.
How To Treat - 1 tablespoon per 5 gallons of aquarium water. Repeat only once, if necessary. Use only “USP” grade Epsom salt.
Pros - Reef safe, as Epsom salt is just magnesium sulfate.
Cons/Side Effects - The effects of excessive sulfate in a reef aquarium are not fully known.
Formalin: Treats Brooklynella and provides temporary relief for Marine Velvet disease (Amyloodinium). Also may be used as temporary relief, or even as an alternative treatment, for worms such as flukes and black ich.
How To Treat - Formalin is very interesting because its potential is not fully known. It is best administered in a bath solution for 30-45 minutes, following the dosage instructions on whatever bottle you use; or at 150 ppm if using "100% formalin" (ex. Formalin-MS). The bath should be done in a large glass bowl or container, and temperature should match the tank the fish is coming from. A bucket is not advised as plastic may absorb some of the medication and then leach it back out during future use. It is imperative that you heavily aerate the bath solution for at least 30 minutes before and also during treatment to compensate for oxygen depletion. The fish should be placed in a premixed bath solution. DO NOT add more formalin after the fish is already in the bath.
For Brooklynella, multiple baths may be required (so long as symptoms persist), but it’s important to give the fish a day to recuperate in-between baths. Formalin has also been used as alternative treatment for external worms such as flukes and black ich. However, at least 2 baths are required (7 days apart) for the same reason described when using Prazipro. For all of the above, post treatment, the fish should not be returned to the same tank/water he came from to prevent reinfection.
You can dose formalin directly in a quarantine tank, but this can be risky due to the harshness of formalin and how quickly it can deplete the water of oxygen. Providing additional gas exchange to the QT is a must! A fish being treated must be monitored closely and should be removed if showing signs of distress - this applies when treating in QT or in the bath solution.
Pros - Treats or provides temporary relief for a wide range of diseases. In some cases, formalin can “buy you more time” until a proper treatment can be done.
Cons/Side Effects - Formalin contains formaldehyde, a known carcinogen. Therefore, precautions must be taken when using it. Preventing your skin from coming in contact with it by wearing water proof gloves and not breathing in any fumes by wearing a face mask is highly recommended. Formalin also can be harsh on the fish and will quickly deplete oxygen from the water. In some areas, the purchase of formalin is prohibited.
Freshwater Dip: Provides temporary relief for Brooklynella, Flukes & "Black Ich", Marine Velvet disease (Amyloodinium); possibly even Ich & Uronema marinum (both unproven). Can be used to confirm the presence of Flukes.
How To Treat - Fill a bucket with RODI water, and use a heater to match the temperature to the water the fish is coming from. Aerate the water heavily for at least 30 minutes prior to doing the dip, then discontinue aeration while performing the dip. Fish aren’t overly pH sensitive for short durations like this, but you can squirt a little tank water into the dip just before the fish goes in to help bring it up.
Place the fish in the freshwater (FW) dip and observe closely. It is not unusual for them to freak out a little at first. Also, tangs are notorious for “playing dead” during a FW dip. The important thing is to watch their gills; they should be breathing heavily at all times during the dip. If breathing slows, it’s time to exit the dip. Dip the fish for no longer than 5 minutes. Multiple dips may be done, but it’s important to give your fish a day to recuperate in-between dips.
For flukes, use a dark (preferably black) bucket so you can see if tiny white worms fall out of the fish (especially out of the gills) at around the 3-4 minute mark. The worms will settle to the bottom, so you can use a flashlight to look for them there as well.
Pros - Provides temporary relief for a wide range of diseases in a chemical free environment. Can “buy you more time” until a proper treatment can be done.
Cons/Side Effects - Not a permanent “fix” for any disease, as FW dips are not potent enough to eradicate all of the parasites/worms afflicting the fish. Some fish can have an adverse reaction to a FW dip by appearing unable to maintain their equilibrium once returned to the aquarium. If this happens, hold the fish upright (using latex, nitrile or rubber gloves), and gently glide him through the water (to get saltwater flowing through the gills again). It is also a good idea to place the fish in an acclimation box until he appears “normal”.
Hyposalinity: Treats Ich (Cryptocaryon irritans) and gill flukes.
How To Treat - Place the fish you wish to treat in a quarantine tank with SG & temperature matching the tank they came from. Over a period of 48 hours, gradually lower the SG down to 1.009. You must use a perfectly calibrated refractometer at all times while doing hypo. Treat for 30 consecutive days, and during that time the SG must always remain at 1.009. If it inches up even slightly, the 30 day clock restarts. For this reason, many people use an auto top off system while performing hyposalinity. Some have even used hypo to successfully rid their display tank of ich, while others have failed. All corals and inverts must be removed beforehand if you wish to try this.
One of the challenges posed by hypo is maintaining a proper pH for the entire duration. While fish aren’t overly sensitive to low pH for short periods of time, anything continuously lower than 7.5 is going to be a problem. So, you will have to constantly test and then buffer the water to raise the pH. This can be accomplished by using supplements (available at most LFS) or you can “bake” your own DIY supplement by using baking soda. Spread baking soda onto a clean baking sheet, and bake at 300F for 1 hour. This process drives off water and carbon dioxide from the baking soda, and the result is an effective pH buffer. You will need to experiment (start with a very small amount) to determine how much is needed to raise your pH to the desired level.
Pros - Chemical free solution to ich, gentle on the fish. Scientific research also showed hyposalinity at 15 ppt for 2 days eliminated juvenile and adult flukes. When maintained for 5 days, egg hatching was prevented.
Cons/Side Effects - Difficult to execute properly, and hypo resistant strains of ich have been proven to exist (study done by Yambot in 2003.)
Malachite Green/Methylene Blue: Treats ammonia burn, cuts, injuries.
How To Treat - Comes in both liquid and powder form, sometimes mixed in with another medication(s). So, follow the directions on the label. Best used as a 30 minute bath solution, but you also can treat with it in a quarantine tank. Aerate heavily. If you are using it in a bath solution, then it is also a good idea to treat the fish with nitrofurazone (active ingredient found in Furan-2 and Nitrofuracin Green Powder) once he is returned to the quarantine tank. Nitrofurazone is great for treating open wounds or sores.
Pros - Highly effective.
Cons/Side Effects - Depletes oxygen from the water. Malachite Green is considered “harsher” on fish than Methylene Blue.
Metronidazole: Treats internal parasites (worms), Brooklynella; possibly Uronema marinum.
How To Treat - Metro can be found as a stand-alone drug (ex. Metro+, Seachem MetroPlex) or incorporated into a multi-purpose medication (ex. API General Cure). It is best to soak it in the fish’s food; however it can also be dosed directly into a quarantine tank. Use until symptoms (white stringy poop) are gone.
Whether or not metro is “reef safe” is a topic for debate. The general consensus is that while soaking it in fish food IS “reef safe,” dosing it directly into the water column IS NOT and should only be done in quarantine.
Pros - Can be soaked in fish food, making it (somewhat) reef safe.
Cons/Side Effects - In my experience, certain fish seem to have an adverse reaction to it. But these are in the minority.
Nitrofurazone: Treats open wounds or red sores.
How To Treat - Nitrofurazone is an antibiotic, and an active ingredient found in Furan-2 and Nitrofuracin Green Powder. Nitrofurazone is great for treating open wounds, and especially those “red sores” commonly seen on butterflyfish and some angelfish.
Pros - Highly effective; found in a number of bacterial disease medications
Cons/Side Effects - Appetite suppression; it has been discontinued in the US (for human use), which may possibly affect its availability for the pet industry.
Prazipro (praziquantel): Treats flukes, black ich, and some internal parasites (worms).
How To Treat - In either a quarantine or display tank, dose Prazipro at the rate of 1 teaspoon per 20 gallons of water. DO NOT OVERDOSE (especially with wrasses), try not to mix with other medications (for various reasons), and provide additional gas exchange while treating with Prazi. Wait 5-7 days, do a 20-25% water change and then repeat dosage. The reason for the second dose is to eradicate the “next generation” of worms before they can lay eggs of their own. Because while Prazi does kill worms, it doesn’t eliminate any eggs they might leave behind.
Prazipro is generally considered reef safe, although it may kill any tube worms/feathers dusters you have. It may also eradicate bristle worms. If you have mass quantities of these, the resulting die-off can lead to an ammonia spike. After treatment is done, activated carbon may be used to remove any residuals (if you need to use a different medication next). If using a protein skimmer post-treatment, be advised that it will “over skim” for at least a couple of weeks.
Pros - Reef safe, effective dewormer that is relatively gentle on most fish.
Cons/Side Effects - Mild appetite suppression, moderate oxygen depletion, wrasses are sensitive to overdosing.
Tank Transfer Method: Treats Ich (Cryptocaryon irritans) only.
How To Treat - Tank transfer (TTM) is probably one of the most underused and underappreciated resources in our hobby. To properly execute TTM you need two tanks (or buckets), with dedicated equipment for each tank (not to be shared between the two). I personally use 2 of the 10 gallon tanks to do TTM, each with its own heater, thermometer, air stone, airline tubing and PVC elbows for hiding places. This is how TTM is implemented:
- Day 1 - Fish is placed in initial QT.
- Day 4 - Roughly 72 hours later transfer the fish to new tank. The time of day you do the transfer is unimportant, but never exceed 72 hours from the last transfer. The temperature and SG of the new tank should match the old one perfectly, so you can just catch & release (no acclimation). Transfer as little water as possible with the fish.
- Day 7 - Repeat.
- Day 10 - Repeat.
- Day 13 - Repeat and done (fish should now be ich free).
Simply put, this process works because you are literally outrunning the parasite’s known life cycle. If a fish is infected with ich, trophonts will leave the fish at some point during the TTM process, and the encysted stage doesn’t have enough time to release theronts (i.e. free swimmers that re-infect the fish) before the fish exits the tank. Ammonia isn’t much of a concern with TTM, because every 3 days the fish is placed in a new tank with new water; or you always have the option of using ammonia reducers, such as Amquel or Prime, in conjunction with TTM since there is no risk of negative interaction because no medications are present. However, you do have the option of dosing Prazipro (if you need to deworm) at the onset of “Day 4” and “Day 10”; transfers 2 & 4 respectively. Just remember if you do this that you can’t use any ammonia reducers while Prazi is present in the water.
One of the cons to tank transfer is the amount/cost of saltwater needed to do it. For example, using my 2-10 gallons I go through 50 gallons of saltwater before the TTM process is complete. However, a thrifty hobbyist can use water stored from a recent display tank water change to implement TTM. Obviously, this only works if you are 100% confident that your display tank is disease free and don’t siphon anything off the bottom. ;-) The other problem with TTM is netting the fish every 3 days. That concern can be somewhat alleviated by using a plastic colander in lieu of a net to catch the fish (square ones work better than round ones):
Pros - Chemical free solution to ich, highly effective when performed properly, can be combined with deworming via Prazipro.
Cons/Side Effects - Cost (if using all new saltwater), time/effort expended, probably somewhat stressful on the fish being caught every 3 days, does not treat other parasites such as velvet, brook, uronema.
Vitamins/Herbal Remedies: Used to boost a fish’s immune system, supplement dietary deficiencies, and improve overall health.
How To Treat - Vitamin supplements, such as Selcon, Zoecon and Vita-chem may be used as food additives. A DIY option is Omega 3 & 6 fish oil. I once saw a thread (with pictures) of a Purple Tang with a bad case of HLLE, where the condition was completely reversed by using Selcon & Zoecon on alternating days; in addition to feeding nori. The value of feeding nori cannot be overstated, as it contains high levels of iodine and fiber. All of the above will aid in boosting your fishes’ immune systems. Soaking food in garlic may or may not be useful.
The “pea trick” is something I want to briefly touch upon. A fish with constipation will have the exact same symptoms as swim bladder disorder. The latter is considered mostly untreatable, but the former may be remedied by feeding 1 or 2 peeled boiled green peas (same kind you & I eat). It is thought that the fiber contained in the peas help to “push things out.”
There are a slew of herbal remedies on the market and many hobbyists mistakenly believe that these will “cure” their fish or tank of some disease. Although they are not capable of doing that, these remedies may help manage the symptoms of a disease - sometimes indefinitely. Herbal remedies accomplish this by boosting a fish’s immune system to withstand the symptoms. Sometimes this strategy works, sometimes not; or sometimes it works for a while and then stops (and the fish dies). It’s largely dependent upon the overall health of the fish (and the tank in general) as well as the severity of the disease being “managed.” Examples of herbal remedies commonly available include Herbtana (for parasites), and PimaFix & MelaFix (for bacterial diseases).
Pros - Reef safe, improves overall health of your fish, may buy you time until a proper treatment (using medication) can be done.
Cons/Side Effects - May lure a hobbyist into a false sense of security, which can delay real treatment options.
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