AQUARIUM DISEASE PREVENTION;
Proven Steps for a Healthy Aquarium (Fresh or Saltwater)
A Healthy Aquarium; Disease Prevention;
Disease prevention is probably one of the most important aspects of keeping a healthy aquarium, although a generalized statement.
My experience maintaining literally 10s of 1000s of aquariums gave me a unique perspective as compared to a pure hobbyist.
What I mean is that I (and my employees) were at many clients' aquariums only once per week or less. Thus, I did not have the luxury of being able to make sure everything was fine with these fish everyday (kind of like the average hobbyist going away for a one or two week vacation and hoping everything would be OK).
In fact, my largest client (the Bahooka Restaurant) was gained because an employee of the restaurant had an Arowana that was sick and none of the medications being advised to her by others were working.
She heard about me through word-of-mouth and I recognized that she had tank conditions that were not healthy. This prevented her fish's own natural defenses from allowing it to recover.
As well the medications sold to her were not the right medicines for treating the illness the fish had.
Her fish got better after correcting these problems and the rest was history (this aquarium service account launched many other accounts for us including a contract with Disney).
*Fish as Pets; Bahooka Restaurant
*Aquarium Medications; How they Work & Choosing the Correct Medication
I later utilized about a dozen aquariums in a room as well as the use of multiple aquariums at my now largest client (Coaster Co. of America).
With these aquariums, I performed many controlled tests where I monitored certain water parameters.
I studied the effect on fish and water parameters of the regular addition of positive mineral ions, filtration methods, UV Sterilization, feeding and more in these tests.
These variables were subtracted/added and measured over time (over 5 years in one test) as compared to control tanks I used.
More recently I have spent 1000s of hours in researching many of the results from my and others tests in order to provide a better explanation of these results.
I do this to separate real fish keeping facts from anecdotal observations that have become increasingly too common with the poor Internet search engine results provided by Google (I suggest DuckDuckGo Search).
Back to the subject; during my time performing aquarium maintenance, I had to look at EVERY parameter and way to keep a healthy aquarium.
I could not keep my customers' fish alive by relying on the many aquarium-keeping myths that still to this day float around in this hobby.
Sadly many that were put to rest many years back such as the Raw Shrimp Cycling method have been resurrected on the Internet by irresponsible websites, blogs, forums, and Yahoo Answers.
Reference: Aquarium Nitrogen Cycle; Raw Shrimp Cycling
Another example of one such myth is one about bio wheels.
This is not to say Bio Wheels do not work, just not to the level of hype they have been made out to be (& this is a very minor myth as to effect on aquarium health compared many of the others still prevalent today).
Reference: “Do Bio Wheels really work”)
More noteworthy myths exist to which I conducted many controlled tests and later research to explain my results.
Just some of these include: the quality of many popular brands of fish foods, filtration, medications use, cleaning procedures, UV Sterilization, Redox Potential, aquarium cycling & water chemistry including the need of ALL fish for positive mineral ions, despite unscientific claims to the contrary in so many Internet posts.
A Couple References:
*Aquarium Redox; The Misunderstood Importance of this Water Parameter
*UV Sterilization; Including the indirect benefit of Improved Redox
This aspect of chemistry along with Redox, The Nitrogen Cycle, and the use of UV Sterilizer are among some of the most misunderstood aspects of aquarium keeping I have found based on conversations, emails, forum posts, etc.
In fact when it comes to water chemistry mineral ions and GH the amount of misinformation in forums and elsewhere is mind boggling, making the Chemistry Article a must read!
Reference: Aquarium Chemistry; Complete Information
What I found is that if ALL points of disease prevention are practiced; the healthier, more colorful, and long-living your fish will be.
I had very few losses and many of my newer customers noticed the difference after switching to my service.
I have had many forums criticize me for trying to scare aquarists into needing equipment such as "true" UV Sterilizers (not the junk sold on Amazon & elsewhere) or for explaining the science in my aquarium chemistry article.
However, I think it is far from that, as everyone should know what all the risks are and every possible way to keep the healthiest aquarium possible.
To put this another way, would it be honest to tell someone that their little goldfish they won at a carnival will do just fine in a bowl and not need anything more? I do not think so.
My test results and research speak for themselves.
I personally have resisted adding disease charts because these proliferate all over the internet & elsewhere.
Many are very “cookie cutter” in their descriptions and can be misleading in my opinion as well as my mentor for aquarium fish disease treatment.
I feel that understanding prevention methods and knowledge of antibiotics, chemical treatments, and organic treatments will go much further in treatment and disease prevention than a disease chart that has a "one size fits all" approach.
I recommend reading the companion article below about Medications/Treatments for more information that will help you make an educated choice when treatment of fish is required, rather than using a “dart on the wall” approach.
Reference: “Aquarium Medications/Treatments; How they work”
Also, I recommend reading some of the specific disease articles such as “Columnaris/ Saprolegnia” and many others found Here (or other disease specific articles found on the internet or elsewhere):
“Aquatic Information, Resources”
Please read on; Each step listed below is an important part of the Aquarium/Pond disease prevention puzzle (in particular steps 1-10)!
If what you want is a healthy successful aquarium, it is important that ALL steps are followed with the exception of step #11 (which is an important step if you are starting over after constant problems).
These steps represent over two decades of tests and controlled studies.
Each time you subtract each of these steps, you lower your chance for success.
Omitting any of these steps or following one or two halfway, lowers your chance of preventing illness in your fish, so if you are frustrated with your aquarium due to constant “issues”, please follow ALL the steps outlined here before you give up on this wonderful hobby!
 Cleanliness (Aquarium Cleaning):
Please see this article for expanded information of these “Reasons”:
“AQUARIUM CLEANING; Reasons for Water Changes”
Another note to regular water changes; these are also important WHEN your fish are sick as well, being performed before each treatment.
These water changes should also include a thorough “wiping down” of the glass (on ALL sides) to dislodge algae or "slime" that can harbor disease pathogens.
Water changes (which includes a thorough gravel vacuuming) are also recommended after a disease cure has been reached, for cloudy water, or after many fishless cycling methods that will often leave a tank with high nitrates (this generally is not as much a problem with the “seasoned filter media cycling method”).
For more information about the Aquarium Nitrogen Cycle, please read this article:
“NITROGEN CYCLE AND AQUARIUM CYCLING; How the Aquarium Nitrogen Cycle Works”
Generally when fish are present, changes over 50% are not recommended as larger water changes can be difficult for fish to cope with large changes in mineralization, pH, etc. (which affect osmoregulation).
Reference: Fish Osmoregulation
This again is where a Sludge Removing Vacuum can be a good idea to lower decomposing organic mulm that can affect water parameters and in turn lower fish disease resistance and even harbor disease pathogens such as Aeromonas.
When fish are not present or if it you believe a larger water change is necessary, as the risk of osmotic shock is lower than that of other issues that may kill the fish are present, a 100% water change may be performed.
However it should be noted that a 100% or even double 100% water changes is not always the answer to a problem with pathogens or similar (such as cloudy water) as even with complete water changes with thorough vacuuming will not remove every Ich tomite, nematode, bacterium, or Saprolegnia zoospore.
Only a tank bleaching/chlorination is 100% sure.
Further Reference: Saprolegnia in Aquariums
As an example of what I am talking about based on my tests/studies, here are a few examples of why water changes are not a 100% positive method of eradication:
Another risk in "too large" of a water change is pH stress if new water alters the pH more than .5 on the logarithmic pH scale. Similar would be oxidative stress from too large a change in Redox.
The above examples are NOT to say that water changes (especially a double 100% water change) do not improve the above situations, it is just that they should not be depended upon to be fail safe.
This is especially true after a fish die out, where the better course of action would be to bleach the tank and then re-start your bacterial colonies.
On the flip side, these large changes may be a good start in taking care of a non lethal detritus worm infestation, bacterial cloud, or even after certain methods of fishless cycling where being 100% certain is either not necessary or less of a concern.
For more about Aquarium Cleaning, please see this article:
“AQUARIUM CLEANING; reasons and methods for water changes”
 Good Filtration/Circulation:
I recommend two filters for redundancy, and I never totally throw out all media, rather I rinse part of the filter media in used aquarium water so as to preserve beneficial (aerobic) bacteria for proper biological filtration (ammonia and nitrite removal).
 Use ultra violet sterilization:
True Level One UV sterilizers prevent many bacterial, fungal, and protozoa diseases.
 Do not over feed! Also feed QUALITY fish foods (not the over hyped brands that dominate the market):
 Watch water chemistry:
While most aquarium keepers understand the importance of the nitrogen cycle and resulting high ammonia dangers of an aquarium that is not fully cycled (if at all), the importance of Calcium, Magnesium and other positive mineral ions (electrolytes) are an often forgotten component of proper aquarium health, however they are ESSENTIAL TOO!
I have little incidence of Dropsy and Swim Bladder infections as well as clearly longer lifespans when these elements were present (along with good feeding practices and regular cleanings).
This is an area I cannot stress enough and there is so MUCH research to prove this yet is so often ignored in anecdotal forums.
Unfortunately since GH test kits do not differentiate between minerals such as calcium that have lost their positive electrical charge and those still positively charged, this is not always a reliable method of discerning this (a GH of 200 ppm may still be lacking the necessary positive mineral ions).
This is why it is important to regularly change water with ionized water (most tap and well water have adequate ionization, while many bottled, RO, DI, and soft water does not), as well the REGULAR addition of minerals via Wonder Shells, Mineral Blocks, AragaMight, SeaChem Replenish or other methods is extremely important. I have personally found that the Complete Wonder Shells are the most effective and simplest method to achieve this for freshwater aquariums (I have also used these or similar products for marine aquariums too).
*Complete Wonder Shells; unique version only at AAP
*Replenish Aquarium RO Mineral Ion Replenisher
*Please note that an aquarium is a closed environment and you cannot expect even with regular water changes, for mineral cations to not get depleted in this closed environment! This is another aspect many aquarium keepers miss, especially those keeping Amazon River or similar environment (biotope) fish.
As an example you must realize that the Amazon is constantly supplied with mineral ions from the Andes Mountains that are then quickly depleted by the acidic soft water environment. Bringing this back to an aquarium, if you immediately drive out all positive mineral ions in a mis-guided attempt to duplicate the Amazon environment, your fish will be constantly deprived of these essential mineral ions!
This is analogous to a person avoiding all sun and then refusing to take any vitamin D supplements.
For more information about this, please read these articles (which include links to many research articles to support my points):
“AQUARIUM GH, KH, Ph, MINERAL CATIONS/ELECTROLYTES”. The section on GH and Calcium in particular is a MUST read for those who truly are interested in preventing disease in their aquarium.
How Fish Drink; Proper Osmotic Function
As to pH, many aquarists will spend too much time chasing a “perfect” pH when a STABLE pH is more important, which I can speak to in the 1000s of aquariums I have maintained at different pH and other parameters. I have seen Discus (a fish which comes from waters often under 6.5) breed in aquariums with a pH above 7.5.
What is stressful is a pH that is not stable therefore a good KH and/or acid buffer is important.
What I have found FAR MORE IMPORTANT is electrolytes and calcium (which will also affect a good Redox Potential) present than a so called perfect pH.
*Back to the Nitrogen cycle; High ammonia and nitrite levels make fish extremely susceptible to infection and will eventually kill the fish outright, of which maintaining an environment conducive to a healthy nitrogen cycle is important. This includes being aware of the dangers of certain medications and realizing that low pH environments are not always conducive to proper nitrification, although at a pH of 6.7, most "total ammonia" is actually NH4 ammonia, but this can change quickly with a any condition that suddenly spikes one's aquarium pH, including a water change resulting in a sudden and deadly conversion of non toxic NH4 to very toxic NH3!
See the chart found in this article:
Aquarium & Pond Test Kits; Ammonia and Ammonium Chart
Prolonged nitrate levels above 50 ppm will stunt fish growth and lower fish immunity. Nitrates (along with Redox) are not a problems for fish health in the short term as ammonia is, however the statement that nitrates are not poisonous is another aquarium keeping myth. Nitrates over 30 ppm have been shown to kill cephalopods and nitrates over 20 ppm (some studies show even lower) have been shown to cause blue baby syndrome in humans, so why would long term exposure to higher nitrates not be detrimental to fish?
Please read these articles for more about nitrates:
* “Aquarium Answers; Nitrates in Aquariums/Ponds”
*Aquarium Nitrogen Cycle
*Although not essential, knowing about Aquarium Redox Balance is another tool for keeping disease free aquarium. The simplest way to look at this is if you have Redox reduction (around +125 to -200 mV), your aquarium water would be like having anti oxidant vitamins in it. I should be noted that if correct cleaning procedures are met (with healthy new water, as not all new water has a balanced Redox), regular mineral cations, and UV Sterilization, your Aquarium Redox is most likely to be fine.
While not easy to understand, more and more studies in human health are showing that properly ionized water with at least a reasonable amount of mineral ions and carbonates will improve immune response and health.
For more, please read this article: “THE REDOX POTENTIAL IN AQUARIUMS (& PONDS) AND HOW IT RELATES TO AQUATIC HEALTH”
The bottom line is that while many aquarium keepers understand the importance of low ammonia, nitrite levels, many do not understand the importance of mineral ions and a stability of water buffering; I cannot emphasize more that your aquarium will never be 100% if your water parameters are not 100%.
What is noteworthy from my decades in aquarium maintenance; when I finally have convinced the service client or a person inquiring via email or forums to properly maintain their GH, KH, pH, minerals ions; most often the constant problems ceased.
For whatever reason, improper water management advice seems to run high among Betta keepers (please take this as constructive criticism if you own a Betta or visit a Betta forum), yet once these water parameters are corrected including the use of properly mineralized water, in most instances the health issues decline or cease all together.
Although this is an area where I have incomplete evidence (this does not mean the assumptions are wrong, just not totally proven), it is still an area where one should not short change your fish. I should also note that this IS a proven area when it comes to healthy anemones and coral in marine aquariums and plants in freshwater. The theory (and also as per my more limited tests/observations) is that the wavelengths that are beneficial for many animals such anemones as well as plants benefits fish in proper assimilation of nutrients as well as aiding in an balanced Redox Environment.
UPDATE: From Redox Potential; As it Pertains to Aquariums
"Recently reviewed and updated tests have also shown the positive benefit of near-infrared to infrared light in the improvement of Redox Reduction and wound healing."
Please read this article for MUCH more about correct aquarium lighting:
“Aquarium Lighting Information”
This is a complex subject that is best understood in full, so I recommend reading the article in its entirety when possible.
I will also add as to lighting, although this is not as important a piece of the fish health puzzle as say Aquarium Cleaning/water changes, it is still a part especially when view as how many aspects of life can be traced back to the sun, even if indirectly. As well this new evidence as per the Aquarium Redox and wound healing further proves the importance of CORRECT lighting for fish only aquariums.
 Too Much Care
This section may sound ridiculous, however in both (admittedly anecdotal) observations of customers who took care of their own aquariums and my own my scientific tests of service clients aquariums I have noted that when a tank is “over cared for” that the end result is a more problematic aquarium.
The bottom line is with the exception of my last comment, I have seen and tested differences in fish health, Redox, water parameters, and more when tanks are “over managed”. Even the last comment has validity even if less testable, so this too should be avoided.
 Fish Old Age or When NOT to Treat:
This is a more subjective subject and is related to the above over care section.
As per medication use in older fish, certainly the use of proven stronger medication therapy is worth attempting, however often a positive response is not forthcoming.
Often with older fish using generally less effective but safer treatments such as Pimafix, Melafix, Bio-Bandage, and especially Medicated Wonder Shells might be considered. The advantage of the Medicated Wonder Shell in particular is that this product adds mineral Cations essential for fish immunity and osmoregulation while providing a safer buffered medication dose.
In the end if the fish ceases to eat, euthanization may be the best recourse.
*Medicated Wonder Shells
*Aquarium Solutions (Hikari) Bio-Bandage
 When you do treat for disease:
For more information about Aquarium Medications, please see this article:
“AQUARIUM MEDICATIONS, treatments, how they work, and which ones to use and not to use.”
 Purchase Fish from a Reputable Source:
This cannot be emphasized more, yet is quite simple, if you continue to have problems with a current source from your fish, try another (maybe you can get a good recommendation from a friend, etc.) If you find a good source, stick with it, even if the price is higher.
 When you purchase fish (Quarantine, baths, dips);
This is also an important step that both retailers and retail buyers of fish often miss the importance there-of.
Additional Marine Fish Acclimation Info:
*Besides the above, I ALWAYS at minimum provide a 3-5 minute pure freshwater dip (acclimated with marine buffers to the correct pH/KH to prevent stress)
This is 90% effective for prevention of Cryptocaryon and Oodinium. Consider the more advanced quarantine below.
Better or for fish shipped over longer time periods (such as fish purchased online or from overseas breeders, etc.)
You need to be even more careful in the acclimation process. Depending on the care given to the fish you are receiving (whether fresh or saltwater), this can take up to a few hours. The usual problems for fish that have spent more than 4 hours in shipping is ammonia/nitrite toxicity and CO2 buildup which results in much lower pH than the water originally shipped in. Once the shipping bag is opened there will be “gassing out” of CO2 resulting in rapid increases in pH which can stress or even kill fish that are already stressed very quickly.
To address this, the shipping bag should only be opened just enough to allow a drip tube so as to slowly drip water from the display (or whatever aquarium will be receiving the new fish) at a rate of a drop every few seconds. I usually place the bag in a bucket/tub of aquarium water so as to slowly temperature adjust and allow for gravity dripping of the water (I use an airline valve to adjust the drip).
If air temperature in the room is much more than 10 degrees Fahrenheit cooler than the bucket being used for this drip acclimation, the use of a Hydor 7.5 watt UG Heater can solve any issues of degrading temperature during this process (or the 15 watt model for full buckets)
I will also add a dose of Methylene Blue as per water volume for ammonia/nitrite toxicity (brown blood syndrome) to the water during this slow acclimation time.
*Lees Air Line Control Valve
*Hydor UG Heaters (these are safe in low water environments, unlike glass heaters)
Here is a new video about new fish acclimation:
Best Acclimation from Fish Store
Obviously time in shipment, amount of food in the fish’ gut at time of shipment, amount of fish and air in the bag will all affect how stressed the fish will be upon arrival especially as per CO2, ammonia/nitrites.
I should note that Kordon makes a “breathable” shipping bag that has quite an internet “buzz” going, however my interviews with several international shippers gives a mostly thumbs down to this product.
Here are a few points (+ or -) about this bag:
+ The bags allow oxygen and CO2 exchange which also lowers pH shock upon arrival.
+ Lowers size of shipping container as NO air needs to be added to the bag.
- The bags rupture easily; many shippers have told me that bag ruptures are triple normal.
- They still do not aid with ammonia/nitrites
- If bags come in contact with each other, they do not work well and packing them for the inevitable rough handling of shipping is nearly impossible or at least very time consuming.
- The bags do poorly with multiple fish per bag, in part because the bags are designed to hold small amounts of water so that fish can come close to the sides of the bags which multiple fish per bags usually does not allow.
- Higher cost.
- The bottom line is that the shippers I asked reported HIGHER losses with these bags.
Do not get me wrong, I think these are a unique idea, especially for smaller individual shipments, however based on my discussions with real world shippers that do not work well.
Cross Contamination of Equipment
As an aquarium maintenance professional for a few decades, this was a major concern and should be for any aquarium keeper who has more than one aquarium.
This becomes even more acute when one adds new fish to one tank/aquarium that this aquarium and any others do not come in contact in any way.
Steps to take (All are Important):
Quarantine or Hospital Tanks
If possible a quarantine or baths are good disease transfer preventative steps.
For a quarantine tank I recommend as large and aquarium as space allows for this, generally at least a 10 gallon (although this is not always possible and even a sterile 5 gallon bucket can work if need be).
Having this tank running constantly OR at least adding aged filter media is very important so as to not have ammonia spikes that will defeat the purpose of quarantine.
I recommend a bare tank with a seasoned Sponge Filter . Running this sponge filter with an air pump is recommended over a power head water pump as the air pump method will provide a more gentle current that is less stressful to new fish.
A saltwater quarantine tank for prevention or treatment may be set using live rock and an air stone for bio filtration.
Product Resource: HydroSponge Premium Aquarium Sponge Filters
It is important to note that when quarantine tanks/hospital tanks are employed that I have aquarists inadvertently cause more stress using this quarantine/hospital due to high ammonia/nitrite levels which is why I strongly recommend keeping a running sponge filter or similar for your quarantine/hospital tank. Simply moving a seasoned sponge filters or a piece or two of live rock from your display tank (for saltwater) is often all is required. If Methylene Blue is used, this may temporarily destroy your bacteria in you bio filter or live rock, however this is still a minor price to pay so as to not add further stress from high ammonia/nitrites, especially when the quarantine lasts more than 48 hours.
For treatment I recommend a Medicated Wonder Shell OR (not “and”) Methylene Blue combined with a Malachite Green products such as ParaGuard.
Monitor ammonia and other parameters (make sure there are no pH swings) while the fish are in quarantine. Generally if your fish come from a good source 48 hours is enough, however up to a week may be needed.
Metronidazole can be added to either the MB/ParaGuard method or Wonder Shell for added Trematode, Nematode, Monogenean Parasite prevention.
*SeaChem ParaGuard Ich, Fungus Treatment, Prevention
*Methylene Blue at AAP
*Medicated Wonder Shells
*SeaChem Metrononidazole; Parasite, Anaerobic Bacteria Treatment
Finally, it is important to cover this quarantine or hospital tank with a towel or similar so as to keep in near total darkness. What this achieves is to calm fish, lowering stress which in fact speeds recovery and/or allows for better disease prevention of new fish arrivals in quarantine.
I also have a theory as to why keeping a hospital tank in the dark often helps considerably (sometimes even main display aquarium); Fish instinctually hide and get stressed for their own fear of being harmed or even killed by other aquatic inhabitants. This then causes fish to often get even more sick from this stress. By calming the fish, both the medications and the fish' own natural defenses can work together for a more quick recovery or sometimes recovery itself when just using medications fails.
Often a quarantine tank is not possible or practical (as in my aquarium maintenance business). This is where a 30-45 minute bath is very useful for BOTH freshwater and saltwater. I would make sure to adjust pH so that there is no pH shock, especially for saltwater fish.
A bath can be performed in as little as 1 quart of water (or even less) or in a 1 gallon Rubbermaid (or similar) container or a small BARE tank (not gravel, décor though). I generally use a 1 quart pitcher with ½ teaspoon of salt and several drops of MB (I also recommend rubber gloves and old towels, rags, paper, etc spread around since Methylene Blue is messy and stains).
For freshwater I would add Methylene Blue at double normal tank treatment strength (as per bottle instructions) then add salt (NaCl) at about 1 teaspoon per gallon (Epsom Salts can also be uses at 1/4 teaspoon per gallon in baths used for treatment, especially in cases of bloat, water retention, selling, etc.)
The salt (regular salt; NaCl) can be increased for difficult treatments, especially with salt tolerant fish such as livebearers (it is best to slowly add dissolved salt to increase levels gently in salt amounts over 3 teaspoons per gallon, even in salt tolerant fish). Generally for most fish (even catfish based on University of Florida studies) 2 teaspoons per gallon can be tolerated for up to 30 minutes (many fish can tolerate 4 teaspoons per gallon), although if unsure about your fish’ tolerance, gradually add the salt via a dissolved solution during the first half of the bath.
A few more tips:
However, if a larger fish is in poor condition and question arises that the fish is already in a severely weakened condition, a bath or better, a dip may be attempted (see below for more about “dips”)
Potassium Permanganate can be substituted for Methylene Blue for treatment baths for ailments such as Flukes, cloudy eyes, & some parasite and bacterial infections. HOWEVER for "pure" preventative baths, ammonia poisoning or unknown problems, Methylene Blue is by far the better choice.
Product Resource: Potassium Permanganate, Clear Water from AAP
See this article under Potassium Permanganate or Methylene Blue for more:
Aquarium Medications; Chemical Treatments
Another key point is that Methylene Blue can quite SAFELY be overdosed as it takes high amounts with long term exposure to be toxic, while Potassium Permanganate should never be overdosed.
For saltwater I would add Methylene Blue at double normal tank treatment strength the Dilute the saltwater to 1.015 to 1.009, making sure your pH stays up by adding any buffers necessary before adding fish (1.009 is a must for Cryptocaryon prevention/removal). The purpose of adding or lowering salt (whether SW or FW) is to change osmotic pressure which is an aid to parasite removal as most parasites such as Ich or Cryptocaryon cannot tolerate these changes as well as fish.
Medications in Baths; Another options to baths is (IN ADDITION to the salts and Methylene Blue, but NOT combined with Potassium Permanganate), you can safely add many antibiotics at double normal recommended dose for the 30 minute bath, this can both increase the effectiveness of the bath and the antibiotic added.
Medications that generally are good choices for baths are;
* Metronidazole which is s good choice for intestinal infections since it is not readily absorbed through the intestines.
* Kanaplex OR Minocyline for Columnaris, Dropsy.
* Nitrofurazone for Columnaris, Aeromonas or Furunculosis
* Usnea is an experimental alternative that has similar properties to Metronidazole and can also be effective for some viruses and possibly tumors. I use about 1 tablespoon per 6 oz. preparation for a 1 quart bath.
Please see this article for more about Aquarium Medications: “Aquarium Medications/Treatments; How they work”
We now have Fish Bath Video, please scroll to the bottom of the page to view
Dips and similar
For known problems (or sometimes as a preventative for new fish from questionable sources) a 5 minute dip is even more effective (albeit more stressful to the fish). In a dip, I again adjust pH and add Methylene Blue, however in the case of the marine fish, I will use a specific gravity of 1.001 for the saltwater fish and a specific gravity of 1.015 for the freshwater fish. This dip should be no less than 3 minutes and no more than 5 minutes to be effective.
A dip is often a better choice than a bath for a large or otherwise “spastic” fish due to the much shorter duration. As well a dip, albeit much more harsh than a bath (when used as described), may be a better choice for a very ill fish that may be “at deaths door” and the risks of a dip are low when compared to the fact of the probable imminent death of the fish. A dip is also a good choice for problems that stem from fluid build-up and poor osmotic function, such as many causes of “Pop-Eye”.
*Another similar idea is to directly swab, drop, or “paint” with a Q-Tip (or similar implement) Methylene Blue, Potassium Permanganate, or Hydrogen Peroxide onto a problem area such as Saprolegnia/fungus, Columnaris, or similar. This can be VERY effective for stubborn external infected areas on a fish.
Potassium Permanganate & Hydrogen Peroxide are generally more effective for the above noted infections, but extreme care should be exercised that Potassium Permanganate does not get into the gills. A quick bath in water with a 2-3 times dose of Prime or similar water conditioner can help if this were to occur by accident.
A generally safe alternative to strengthen the Methylene Blue swab/paint is to mix equal strengths of Methylene Blue and Maracyn Plus (Sulfamethazine and Trimethoprim), then use this to gently swab onto infected areas of a fish
Product Reference: Maracyn Plus from AAP
For an expanded article about Fish Baths & Dips, please see this article/post from Aquarium Answers:
Fish Baths/Dips -for supplemental (& even primary) treatment of Bacterial infections, wounds, sores, Fungus (Saprolegnia), parasite infestations & more
A FEW HELPFUL CONVERSIONS
(use accurate teaspoons, not silverware):
*Teaspoon = 4.929 mL
*Tablespoon = .5 fl. oz. = 14.787 mL
*For mixing salt for a dip; 1/2 dry cup will make a specific gravity of about 1.023- 1.025; For 1.015 specific gravity for a dip, use approximately 1/3 dry cup.
 Aquarium Sterilization (Using Bleach or Salt);
Without trying to sound too modest, I rarely had outbreaks of even common diseases such as Ich in the 100s of aquariums in my care (discounting my LFS quarantine system), as I was VERY careful to take EVERY step in preventative care which includes the right water parameters for the fish kept (such as a KH of 50 + and GH of 100+ for general aquariums and 240 + for livebearers), regular and PROPER water changes (proper meaning good vacuuming procedures even in “live sand” of reef tanks that many say should not be performed, the key is the correct way), good feeding practices with a varied and healthy diet, and finally the use of properly installed well made UV Sterilizers (not the cheap UVs sold by many internet retailers for $40).
Fish Bath Video
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