Salt is a normal component of many fish systems. Saltwater and brackish systems require salt on a continual basis. But what about freshwater systems? Some internet pages recommend keeping salt in koi/goldfish ponds/tanks at all times. Others say don’t bother. What are the effects of salt on an all-freshwater species?
In a freshwater environment, a fish’s body is more dense than the surrounding water. As a result, water is constantly trying to enter the fish’s body and achieve osmotic homeostasis. A fish’s gills, kidneys and urinary systems are responsible for removing the excess water. When these mechanisms are compromised, the clinical manifestation of “dropsy” can occur. By adding salt to the water, you are changing the osmolality of the environment surrounding the fish, thereby decreasing the amount of water diffusing into the fish. Some people figure this is less stressful for a fish, but after millions of years of evolution, it really isn’t necessary. A fish’s body can handle the metabolic demands of freshwater. It’s the human equivalent to drinking less water so your kidneys don’t have to work as hard.
Most salt-avid fish keepers will keep their fish in very low salinities: 1-1.5%. This level can be very hard to test accurately for and will often vary between 0-3%. This level will not hurt your fish. If you feel like you NEED to have salt in there, that’s fine, but you should not strive for levels greater than 2%.You do NOT HAVE to add salt to your freshwater fish system. Always add non-iodonized salt (not table salt)!
For some parasites, depending on the species and water temperature, higher therapeutic levels of salt can be used to treat the infestation. Salt works by first increasing, then depleting the mucus coat, which many parasites use as a food source and for protection. Once the mucus coat is gone, the single-celled parasites rupture from the changing osmotic gradient. But if you are slowly bringing your salt levels up without realizing it, some parasites have been found to become resistant to therapeutic salt levels, requiring treatment at even higher doses. The higher the salt dose, the harsher the treatment for the fish.
All in all, a little salt is fine, but don’t obsess over it. Your fish will do just fine without it. The only time we recommend salt is for recovery from trauma or surgery. Don’t forget that salt can kill aquatic plants!
Read along with us as we share our exceptional surgery cases!
Lemon is a ranchu goldfish who was adopted with a slight oral deformity. Once day, when going after a large pellet, one side of her mouth luxated and obstructed her oral cavity. Dr. Sanders was able to correct the injury with a few well-placed sutures and Lemon was able to recover. Read more about her story here.
We don’t know why he did it, but Rocky, a shovelnose catfish, decided that the rocks at the bottom of his tank looked particularly tasty. He ended up eating almost a pound of them and they got stuck in his stomach. Dr. Sanders performed surgery to open the stomach and remove the rocks. Read more about Rocky here.
Our buddy Sparky presented with a HUGE tumor on his eye. Rather than trying to cut the tumor away from the delicate cornea, Dr. Sanders elected to remove the eye. Sparky healed up great and you can never even tell an eye was there to begin with. Read his full story here.
How do fish veterinarians decide when it’s time for a fish to go under the knife? Surgery can be very beneficial for fish when it is warranted.
Water Quality Testing
Prior to any surgery, a veterinarian MUST test the water quality. If the water quality is off in any way, recovery after surgery will be hindered. Corrections to water quality must be made prior to any procedure.
In dealing with structures including and next to bones and the swim bladder, radiographs, commonly called “x-rays,” provide great diagnostic info. These are very handy to see if there is any air where it shouldn’t be and if any structures are not in the correct place. For soft tissue, we need…
This tool is one of the most beneficial to evaluate internal structures in fish. For koi, it is how we are able to see gonadal sarcomas and how extensive they are. A small tumor is much easier to operate on that a large one.
Unlike many other pet species, bloodwork is not very useful in many species of pet fish. Reference ranges have been established, but some are too wide, and vary based on water quality and genetics. For surgical procedures, a PCV (packed cell volume) is helpful to understand how much blood a fish loses during a procedure.
Other than constipated goldfish, “swim bladder disease” is a very common home diagnosis. Or the more common vernacular, “My fish has swim bladder.”
Well, all fish have swim bladders, so that fact is correct, but it is not a disease. “Swim bladder disease” is most common in goldfish and koi, with a high percentage in fancy varieties of goldfish. For 99% of koi, swim bladder disease is caused by poor water quality. I have had one case of actual swim bladder disease in ONE case, shown below.
For this koi, her swim bladder is full of an sterile, non-cellular fluid. We don’t know why this happened, but it causes her to scoot around on her belly. But this is our ONE case of an actual swim bladder issue in a koi. We have had two instances of koi with tertiary swim bladders, but not causing any clinical signs.
For goldfish, 90% of our “swim bladder” cases are lethargy secondary to poor water quality. Most of our actual swim bladder cases are fancy goldfish with most likely structural deficiencies. We’ve illustrated this point previously with our case on red moor, Huxley. Compare this comet x-ray below…
To these fancy goldfish…
Goldfish are supposed to have a two chambered swim bladder, but due to their anatomy, these fancy varieties have limited space in their coelomic cavities. This sets them up for buoyancy issues from birth.
Goldfish and koi are also physostomous fish, meaning that they inflate their swim bladders by having a pneumatic duct between their esophagus and swim bladder. When they eat at the surface, it encourages air to enter the swim bladder. This is the main reason we see swim bladder issues. Goldfish are voracious eaters and if too much air gets sucked in, they can have positive buoyancy issues.
Fish with negative buoyancy may not have enough room in their body to support a larger swim bladder. However, being negatively buoyant is much safer than positively buoyant. Fish stuck at the surface are prone to air ulcerations where the skin starts to break down by being exposed to long periods of air.
External floats, such as those praised on YouTube, must be designed with the fish’s external surface in mind. Anything that rubs up against the skin will disrupt the protective mucus coat and cause secondary infection. Any float attachment will be TEMPORARY. We only apply them to get fish the surface to naturally inflate their swim bladder. We can take air out surgically, but we cannot add it in case the swim bladder ruptures.
If your fish is showing signs of negative or positive buoyancy, CHECK YOUR WATER QUALITY FIRST. Only 10% of our goldfish cases are primarily caused by the swim bladder. The other 90% are water quality, diet, maintenance or bullying/trauma. Do NOT add a float without proper surgical prep in order to minimize infection.
It’s almost koi season at Aquatic Veterinary Services! Here are our most common diseases we can expect to see and the signs you should be aware of if any of these diseases are present in your pond.
5. Carp Pox
Although not THE koi herpes virus, carp pox is also known as cyprinid herpesvirus-1. It causes lesions within the skin that can look like “candlewax drippings” and “frosting” along the leading edges of the lips and fins. In cooler water temps, the lesions can be severe, but as the water warms, the fishes’ immune system and skin replacement can make the lesions almost vanish. Only in severe cases will a fish start to be compromised to secondary infections.
Since this is a herpes virus, there is no treatment or cure. If you have one fish in your pond that is showing these clinical signs, all of your fish have already been exposed. Only immune-compromised or stressed individuals will show clinical signs.
This is a very common disease for us to diagnose. Unless the case is severe, the fish will have good health, but will not be very pretty.
4. Monogenean Treamatodes (aka ‘flukes’)
These irritating little worms are most commonly gyrodactylus or dactylogyrus species. They can infiltrate the skin or gills and cause severe irritation for any fish. You will most commonly see signs of skin irritation, with increased redness on paler fish, bruises or missing scales.
Since fish cannot itch themselves like a cat or dog, they exhibit a behavior known as “flashing.” Usually, you will see your fish throw themselves sideways along the sides or bottom of their pond in an attempt to dislodge these irritable invaders.
Severe infestations can cause the gills to shut down and death to occur. There are many over-the-counter medications that will claim to take out these bugs. Please keep in mind that these medications are not controlled or overseen by any government checks. A veterinarian can prescribe a prescription-strength medication to take care of your problem safely and easily.
3. Gondal Sarcomas
Unfortunately, we often do not catch these tumors in time for surgery. Females between 8-12 years of age seem particularly more susceptible. Our Spring Pond Package for 2019 will include ultrasound screenings for all females since we are trying to catch this disease early.
These space-occupying tumors most likely start from female gonadal tissue. By the time they are visible externally, most of the internal organs are failing. These masses are very hard to catch, which is why our new screening system will be started this year. If caught early, the tumor can be removed via surgery.
This aggressive “scrubbing bubble” is often aided by our #1 disease in koi. We tend to see this parasite most commonly, often displaying the same “flashing” behavior as our monogenean friends.
This parasite is easily treated by our prescription-strength medication. Over-the-counter medications do not work well against this parasite for some reason.
1. Water Quality
I know it is not a “disease,” but poor water quality is the #1 diagnosis for disease I make. Having poor water quality makes all diseases WORSE, including bacteria, fungi, parasites and other pathogens.
Water quality is directly linked to fish health. Like the air we breathe, the water a fish swims in has a direct effect on their overall immune function. Before the spring diseases come, get your maintenance routine overhauled and test your water chemistry regularly to make sure your fish have their best chance for a healthy spring.
Tomorrow, March 13th, 2019 will mark Aquatic Veterinary Service’s 6 year anniversary. It has been quite a year for us, moving out of a bad location into a new facility and getting ready for some new changes and challenges. We’ll be sharing those new updates with you later this week.
In a business where there is no framework, no forecast, no front runner to look at and play off of, you make a lot of mistakes. I have no regrets from any of the mistakes I made along the last 6 years. I only hope I can pass on what I have learned to the next generation of aquatic veterinarians.
In the veterinary community, veterinarians who are able to practice on fish are exceedingly rare. In most veterinary schools, aquatic topics are barely covered, if at all. When I went to Tufts, we had 2 lecture hours on fish. We had 4 on marine mammals for comparison. But most veterinarians out practicing may have no exposure to fish. Of all the veterinarians who see fish, most are involved in mixed private practice, aquarium/zoo work or aquaculture. Those private practices seeing only fish – 2. Myself and a colleague in Texas are the only two veterinarians in the country dedicated to solely helping pet fish.
As our yearly reflection goes, I will answer the most common questions I have been answering on a regular basis.
Question #1: Do you make any money doing this?
Our first few years? Not really. Our last few years as we continue to grow and word gets out. Absolutely, yes. If this job path didn’t show at least minimal feasibility after the first few years, I wouldn’t be here today. In growing a business that has NEVER been attempted before, one has to be aware that it will take considerable more time. We’re in the business of changing how people think about veterinary care, which is a slow process. The general population knows to take a sick cat, dog, horse, bunny or snake to the vet. It is still not common knowledge to take your fish to the vet.
In conclusion, I am making money. It’s not comparable to a small animal vet at this point, but if our trends continue as they have over the next few years, we will surpass them. It’s a marathon, not a sprint.
Question #2: Why are you doing this?
I got into aquatics when I was in undergraduate school at URI. I had time to complete >1,500 volunteer hours at Mystic Aquarium, where I learned all about the fascinating world of fish. I always wanted to learn more about their care and keeping. I entered veterinary school figuring I’d end up at an aquarium, but I was hesitant to be a part of a bureaucratic system. In private practice, one of the best parts is I get to call the shots. From what I have seen over the last 6 years, there is a great need for fish veterinarians. The biggest hurdle is linking sick fish with veterinary care, not the internet. For more on my background, read our famous article, “Why A Fish Vet?”
Question #3: What is the biggest challenge in your field of veterinary medicine?
Dr. Google has never received a medical degree of any kind. Still, owners trust the internet more than a veterinarian’s perspective. Why? Because it costs real money. Sorry, but you get what you pay for. Free advice without any education or expertise ends up in a lot of dead fish. New fish owners are the worst offenders and will often drop out of the hobby entirely after the first big disaster. Now, many of these people simply don’t know that fish veterinarians exist. We have tried to build up our website to catch these people before they fall down the internet rabbit hole, and after 6 years and 200 fish articles, it’s starting to gain speed. For those of you regular readers, we rely on you to share your knowledge of fish veterinarians with your friends, family and neighbors. Our specialty will continue to struggle because no one knows we exist.
Question #4: What is the best thing fish owners can do to keep their fish healthy?
“Maintain your water quality” will likely be my catchphrase for life. Maintaining your aquatic environment for your fish is the most significant contribution to your fishes’ overall health. It comes down to keeping up with your regular maintenance. Most problems occur when people get lazy and skip a cleaning, or two, or all of them. We recommend you put it on the calendar and make it a priority. For everything you’d ever want to know about water quality, check out this free webinar.
So as we cross into our 7th year of service, we thank all of you for your continued interest. We strive to help all fish owners, no matter what the species or where you are. If you have any topics you would like discussed, please let us know. We thank you for your dedication to fish health.
Sincerely, Jessie Sanders, DVM, CertAqV
Interested to see how veterinary and human medicine education measure up? Watch Dr. Jessie Sanders and her sister, human surgeon, Dr. Bailey Sanders, compare their experiences.
We’ve made it all the way to our #1 mistake new fish owners make: not asking for help when you’re over your head. A new hobby can be very challenging and there’s no shame in getting assistance if you’re overwhelmed.
But, as we covered with mistake #3, not all sources of help should be treated equally. Just because somebody wrote it on the internet, does NOT make it true. Cause and effect can be misinterpreted and hobbyists are known for corroborating evidence that is not connected. Here is a common example:
Owner A buys medication from store B, which claims it can cure their fish of disease C. The medication, be it anti-parasitic, anti-bacterial or anti-fungal, requires multiple doses with multiple water changes in between. Owner A uses medication as prescribed and the fish gets better. Since 90% of our clinical cases are secondary to poor water quality, it is more likely the increased water changes cured the fish, NOT THE “MEDICATION.”
But, you see this on the internet and think it must work for your fish with the same issue. But your water might be different with a different species of fish and a different pathogen (bacterial, parasite, fungus). All that you can see is how your fish is behaving, which sounds similar to Owner A.
Too many owners reach straight for the treatment without a diagnosis. You just want to make your fish healthy – NOW. Your water looks fine, so it can’t be the water. And this is where many fish owners fall out of the hobby. They try X number of medications, read all they can on the internet, but without a diagnosis, the fish will eventually perish.
What about calling your aquatic veterinarian?
We understand it is a foreign concept for many. One of our colleagues starts many of his professional talks by asking the following question:
If you walk up to 100 random people on the street and ask them, “my fish is sick. What do I do?” What are the top 3 responses?
A. David Scarfe PhD, DVM, MRSSAf, CertAqV
The pet store
No where in that list is “call your veterinarian.” Well, it’s time to not only add it to the list, but make it the ONLY response. If you need help with your fish, CALL AN AQUATIC VETERINARIAN. (Click link for a vet near you.) If you have a veterinarian for your cat/dog/horse/etc, see if they are interested in helping. They can directly consult with an out-of-state aquatic veterinarian to help your fish. Have them call us! If you are in California or Nevada, CALL US and we will help you! If you want to pay for our veterinarian’s license in a state we do not cover, CALL US. If you are not in your state and need help, CALL US. We cannot guarantee we’ll be able to give you more than basic husbandry help, but WE WILL HELP YOU AS BEST WE CAN.
The #2 Mistake – Not Doing Your Regular Maintenance
Fish are not maintenance free pets. Many owners think this when they first start, but some fish systems require the same care and cleaning as any other pet. Especially when you are first starting out, it is important to keep up with your regular scheduled cleaning. Maintaining a regular maintenance schedule for your aquarium will be of the most benefit to your fish by keeping your water quality within appropriate parameters.
Our best advice: add your regular maintenance to your TO DO list and make it a priority. Get the whole family involved and take the time to give your fish a happy, healthy home. Here is a helpful checklist for everything you need to do on a daily, weekly, monthly and yearly basis.
If you follow the above checklist, get the family involved and make fish care a priority, your fish will have a long, happy life. If you’re confused or unsure the best way to clean your tank, watch our Best Tank Cleaning Practices video.
The #3 Mistake – Relying Too Much on Internet Searches
The internet is a wonderful, magical place. Because if it’s published on the internet, it must be true, right? Sorry to tell you, but Dr. Google does not have any sort of medical degree. Have you read all about the magic of tiny green peas and the dreaded dropsy disease? Sorry to tell you, but these are just internet fabrications. The veterinary community is partly at fault, having ignored the plight of fish owners for far too long.
Enter Aquatic Veterinary Services!**Wearing a cape, if a business could.** Our mission is to give you the straight, well-researched facts about all things fishy. Does it cost you anything? NOPE! We have over 200 articles on different fish species, diseases, physiology, water quality, surgery and beyond in our Fish Health 101 section. We have a YouTube channel dedicated to more in-depth information and monthly free webinars open to all. Need to waste 10-20 minutes and want to learn something about fish? Pick out a topic here.
There is some good help on the internet, but always consider the source. What worked for one fish under certain conditions does not work for every fish. Disease does not progress the same in every situation. Over the counter medications are not always what they say they are. There are NO regulators checking up on fish medications on pet store shelves.
If you need more help than our website can provide, call your local fish veterinarian. NEVER attempt treating or performing surgery on your fish or your friends/family pet fish. Visit the American Association of Fish Veterinarians to find a vet near you. If you are in California or Nevada, we’re here to help you directly. Call us at (831) 728-7000.
Ponder the following situation: you have two glasses before you. One is tap water and the other is hydrochloric acid.
How do you know which one is safe to drink by looking at them? Which one would you put your fish into?
It is impossible to tell if water is safe for fish by the look of it.
Water that is safe for fish and dangerous for fish will look EXACTLY THE SAME. This is why we always test the water at all of our appointments and why all fish owners should do the same. Fish health is directly tied to certain water quality parameters. If you’re a regular reader, please, list them along with us:
You don’t have to test all of these parameters all the time, but regular tests of AT LEAST ammonia, nitrite, nitrate, pH, kH and temperature are essential.
Test your water AT LEAST once a month. You will need the following tools:
All of these tools are easily purchased at your local pet fish store or online.
Safe levels for fish will vary on the species. For koi, goldfish and most tropical, including bettas, you want your water within the following parameters (please keep in mind that this chart was made using the API kit parameters and are general guidelines):
As your fish systems progress, record your weekly/monthly readings and watch for any trends. How does your regular maintenance change your readings? By keeping a close eye on your parameters, you can significantly improve the overall health of your fish.