Effects many fish from marine and freshwater environments, however, most common in South American and Central American cichlids. Tangs (saltwater) and Koi also seem to have a high rate of occurance.
Cause
Unknown. Many publications, both online and in books, list flagellate protozoans Hexamita and Spironuncleus as being sometimes present. Other possible causes include: Inadequate nutrition, bacterial infections, poor water conditions1.
"Nitrates have been linked in some studies to the development of HITH where a fish is kept for long periods of time in water with levels exceeding 40 ppm." (Danga, 2009)
"A link has been found between the development of HITH and a lack of calcium, phosphorous, and vitamins C & D. Many of the common fish foods sold in the hobby today are enriched with vitamins to make them more balanced, though supplemental vitamins can be added to them as well. Know the diet of your fish and be consistent, and varied. As a side note for carnivorous and semi-carnivorous fish such as Oscars, red devils, and Jaguars, feeder fish should never be chosen as a primary food source because they have virtually no nutritional value." (Danga, 2009)
Many sources have named "boring diet syndrome", where the owner feeds only 1 kind of pellet or flake to their fish for yearsm and the fish develops a nutrition deficiency in response. To help combat this, add new pellets, including veggie and different protein and lipid combinations to their diets, along with the occasional vitamin supplement.
Symptoms
Easily recognized by scabby indented wounds in the head area (see below). May develop along the lateral line as well, which is known as Lateral Line Erosion. (note: HLLE and Hole in the Head are considered the same disease by some, however, I have chosen to keep them separate as there seems to be varied opinions on this).
This is my third article in a series known as "Good To Know" (abbr. GTK), where I will research and attempt to clarify some common mistakes, myths and fish hobby anecdotes for those who are new, and for the vets who have always wondered what information is truly correct and reliable.
The main theme of this article is to help both new and seasoned aquarist understand the bacteria in their tanks. A large amount of misinformation currently circulates the “non-fish junky” level of aquarist population, leading to poor maintenance, understanding and tank husbandry. Dr. Tim Hovanec, a microbiologist and fish hobbyist, is currently the leading mind in this field and thus, will be considered the primary source for information regarding bacteria in aquariums. Dr. Hovanec is best known in the community as Dr. Tim, and will thus be referred to as so through this article.
There is a difference between Nitrifying bacteria, and Sludge Degrading bacteria in aquariums. Many hobbyists will mistakenly confuse the two, especially in times when cloudy water is an issue. Often, hobbyist will be told that the bloom is actually Nitrifying bacteria which is exploding in number due to a waste issue in the tank. This is only partly true; the bacteria you are seeing is exploding in population due to excess waste, but this bacteria is a different type of bacteria and is sometimes referred to as “bad” bacteria because it can out compete Nitrifying bacteria1.
Not all “Bacteria in a Bottle” products are made the same. When Dr. Tim began researching his PhD dissertation, he made some pretty important discoveries regarding bacteria in aquariums. Dr. Tim, in an interview with Mr. Saltwater Tank entitled “Bacteria in a Bottle: Snake Oil or Worth Trusting”2, commented on how he came to understand why many of these products were failing: “All the nitrifiers had bacteria that came from waste water treatment, they didn’t have aquarium bacteria, they’re the wrong ones. They [customers] would add the bottle and think ‘oh, they’re all dead’. No, they’re the wrong bacteria. They are all nitrifiers, but certain nitrifiers live in high ammonia and high nitrite concentrations like a wastewater treatment plant. We don’t have those concentrations [in aquariums]. We have very low concentrations. That’s a different species of ammonia oxidizer and a different species of nitrite oxidiers”. Dr. Tim explains he was looking for the old-school bacteria (Nitrosomas europea And Nitrobacter sp.) but found none or very inconsequential amounts, and ended up concluding that it was Nitrosomas marina which oxidized ammonia and Nitrospira sp and Nitrosococcus sp. which converts Nitrite to Nitrate in a healthy aquarium. Dr. Tim’s bacteria, which have gained a good reputation online, can be ordered online at: http://store.drtimsaquatics.com/ or can be found at other hobby related retailers.
Tetra SafeStart is the only product, other than Dr. Tim's One and Only Live Bacteria, known to carry the proper cycling bacteria. Most other products carry the water treatment plant bacteria which is useless in low concentration environments like and aquarium.
Photo Credit: AquariumWiki.com
Sludge degrading bacteria are not, in most cases, beneficial to aquariums. Sludge degrading bacteria have a limited role in a healthy aquarium. While these bacteria do eat organic compounds (such as fish mulm), they should be used in conjunction with a bottle bacteria product (see below) or water changes as these bacteria only break down waste into ammonia. Test your tank when using these products to ensure that your tank can handle the excess ammonia and convert it quickly.
Sludge degrading products also have an added benefit whereby they out compete “bad” bacteria by cultivating a much less harmful species. This is called Competitive Exclusion, which is defined by AquariumWiki3, “By adding known harmless waste eating bacteria in large numbers the added bacteria out competes any existing bad bacteria for the nutrients in the tank and therefore is a safe and effective way to starve off infectious bacteria. In the medical industry this technique is called 'bacterial interference' and is used to displace pathogens by using harmless bacteria.” These types of products are usually referred to as “Zymes” such as Stress Zyme by API, yet some Waste reduction products also have this added effect.
Never overdose these products as the new bacteria can starve out your good bacteria through oxygen and nutrient depletion causing a tank crash.
Example of a product which contains sludge degrading heterotrophic bacteria.
Photo Credit: SwellUK.com
Boil your dried out filter media to help ward off bad bacteria. Unfortunately for hobbyists, the good nitrifying bacteria cannot survive when dried out. However, the bad heterotrophic bacteria can4. To ensure that the good bacteria has a fighting chance at colonising all your media, boil and bacteria housing media once it has dried out to eliminate the bad bacteria. Also, any media which has been standing in stagnant water for more than approx. 15-20hrs without oxygenation should be boiled in ideal circumstances.
Forget the shrimp rotting method of cycling.
So we’ve been discussing how so called “bad” bacteria can out-compete good bacteria for nutrients, oxygen, and space. By using a piece of shrimp, you are indeed adding a source of ammonia, but first, you are stimulating a massive explosion in growth of organic compound devouring bad bacteria, which will quickly colonise much of your available media and tank before the good bacteria can find a place to begin breaking down the subsequent ammonia spike. Aside from this competition aspect, a full grown shrimp in a sterile tank will likely cause an ammonia spike over 5ppm5, which actually inhibits the growth of good bacteria. Which brings us to our next point…
When cycling a tank, keep ammonia below 5ppm. As we’ve just mentioned, Dr. Tim explains in Episode 22 of Aquariumania on Pet Life Radio5, that having an ammonia reading above 5ppm can actually inhibit the growth of nitrifying bacteria. In extreme cases, Nitrosomas europea bacteria can become the dominant species, which will not be sustainable in a low concentration system like an aquarium. Thus, the cycle will be prolonged as some high range ammonia oxidizers come and go and the real aquarium bacteria takes hold. If your ammonia level reaches over 5ppm, do water changes to correct this problem.
Environmental conditions can effect the quality of bottled bacteria. Dr. Tim states on his website6 that, “Environmental conditions can cause bad batches. The first condition is being exposed to temperatures outside the range they can survive. If the liquid in the bottle freezes the nitrifying bacteria are killed. It don’t matter the brand – freezing kills the nitrifying bacteria. High temperatures also can kill or damage nitrifying bacteria. If the bottle is exposed to 110°F for a day or so the bacteria can be killed. Prolonged exposure to temperatures over 95°F drastically reduces the shelf life of nitrifying bacteria.” Dr. Tim goes on to recommend checking the best before date and also explains that refrigerating the bacteria can help keep the bacteria fresher and more viable longer.
Mr. Saltwater Tank's interview with Dr. Tim.
This concludes the beginner portion of the bacterial article. For those wanting to dig deeper into the subject, I will be posting a new article which discusses the more advanced topics such as Autotroph vs Heterotroph, Probiotics, Vodka dosing, Denitrificaton, Building a denytrifier, Nitrosomas Europea vs Nitrosomas marina and Faculative vs Obliogated Hetertrophs. For more information on some of the products mentioned, an article explaining the use of common aquarium products is also in the making.
Some absolutely amazing DIY skills. Love the fish selection. Happiest tangs I've ever seen! Not much in the way of coral, or updates, but still a great thread to read through and enjoy.
This is my second article in a series known as "Good To Know" (abbr. GTK), where I will research and attempt to clarify some common mistakes, myths and fish hobby anecdotes for those who are new, and for the vets who have always wondered what information is truely correct and reliable.
The main theme of this article is to help new brackish tank keepers learn the basics behind keeping their organisms healthy. This article was largely inspired by the huge influx of questions I've recieved at work about Green Spotted Puffers and Mono Sebaes, and some of the misinformation currently prevelant in the hobby. I would like to start off by acknowledging Cody Schoup's informative article on brackish tanks, titled: Starting a Brackish Aquarium. This article has been around since at least 2005, when I started my first tank and was the perfect launching pad.
10 Things You Need To Know About Brackish Tanks
Photo credit: US National Oceanic and Atmospheric Administration
1. Brackish tanks are ecosystems which comprise of fish and organisms found in places where a freshwater river meets a saltwater ocean or sea. In the wild, rivers flow down (when applicable) into the ocean. Somewhere along the lines, the freshwater from the river slowly mixes and increases in salinity as it approaches the mouth to the ocean, passing through brackish environments like salt marshes and mangrove lagoons.
2. Brackish tanks require marine salt, rather than commonly sold aquarium salt. Marine salt is just that – it is salt which has (in most modern synthetic salts) been manipulated to include many extra carbonates found in seawater, such as calcium, which effects the water column’s Alkalinity, pH and gH. Marine salt produces saltwater which is chemically similar to water from the ocean, which is exactly what a brackish tank requires. Regular aquarium salt, or simply Sodium chloride, only makes up approx.. 77% of this blend and should be used for medicating freshwater fish rather than used as a means to keep brackish or marine fish alive and healthy. For more information on distinguishing these two salts, click here: Marine salt vs Aquarium salt.
3. Brackish tanks can be filled with a huge collection of fascinating fish. Cody Shoup of Badman’s Tropical Fish, commented in his article Starting a Brackish Aquarium1, “These brackish waters are home to an amazingly diverse and unique group of animals, some of which are commonly available to keep in the home aquarium. These fish include archers, scats, monos, certain livebearers, gobies, and others.” The following are a collection of images with corresponding care pages linked by clicking on the name above.
4. True freshwater plants, like true freshwater fish, suffer from too much salt and will not tolerate brackish tanks. However, with that being said, there will be a few which can tolerate saltier conditions. Schoup explains that Java Fern and Java Moss will survive in a low end brackish tank, however, “After raising your specific gravity over 1.015, these plants will begin to die off and they should be replaced with marine algae such as Caulerpa”2. Most freshwater plants, especially those coming from low TDS and low salt, acidic water (Amazon), will not tolerate even small amounts of salt. Some fish, such as livebearers from the Yucatan estuaries of Mexico (Mollies) have evolved to live in brackish or even marine ecosystems. In general, most brackish fish can live in freshwater at the beginning of their lives, and saltwater at the end of their lives, but should spend most of their time in brackish tanks where they will feel less osmotic stress.
Laguna del Mar Muerto, one of the areas Mollies are native too. 3
Photo credit: La Mana de Cordoba.
5. Yes, that Columbian catfish you’ve always wanted belongs in brackish water! Columbian catfish/sharks are one of the most intriguing fish commonly sold in pet stores. Unfortunately, not all staff members are aware of their long term needs. While sharks can live in full freshwater as youth or juveniles, they will quickly require a higher salt content. Here is an interesting post about the Columbian sharks need for salt and the osmoregulation process, by member water_baby83 on the popular fishkeeping forum Monsterfishkeepers.com4, “…sharks have hit upon a different strategy. Instead of being less salty than the sea, sharks store certain metabolic wastes (namely, urea and trimethylamine oxide, or TMAO for short) so that their overall 'saltiness' is actually slightly greater than that of the sea. As a result, sharks do not continually lose their bodily supply of freshwater to the sea. Instead, any fresh water they need diffuses gently into their bodies through the mouth, gills, and other exposed membranes. Any excess water in a shark's body is filtered by the kidneys and excreted out an opening called the 'cloaca', located between the pelvic fins (the rearmost paired fins, behind the shark's belly). It's a very elegant solution to a significant environmental challenge. But it has its limitations.
If a typical sharks were to swim its very 'salty' body into fresh water, so much fresh water would diffuse into its tissues that the kidneys would have to work overtime in order to get rid of it all. This is a very energy-demanding process, and explains why most sharks do not enter fresh water: it's simply too much effort to keep excreting all that freshwater. But some sharks, such as the Bull Shark (Carcharhinus leucas), are able to enter fresh water for prolonged periods. They achieve this neat trick by greatly reducing their bodily concentrations of urea and TMAO. Even so, a Bull Shark in fresh water is slightly saltier than its surrounding environment, so that it must continually excrete excess water in the form of dilute urine. In total, some 43 species of sharks and rays spend at least part of their lives in fresh water. But one family of South American stingrays -- the so-called River Stingrays (Potamotrygonidae) -- evolved from a marine ancestor to become thoroughly adapted to living in fresh water. So much so, in fact, that their bodies have lost the ability to manufacture urea and -- if placed in full-strength seawater, they quickly die. Though CS may start life in fresher waters, once they are older, they no longer to adapt as well to variations, and will need a more brackish setting. You need to acclimate them SLOWLY, raising the salinity very slightly over a period of several weeks for the best results. It's not too complicated, but you do need to be patient, as in the wild, they do not just up and leave the freshwater and jump into salt. They hang around inlets, and such, gaining a tolerance, and acclimating themselves. Just take your time, and do it slowly, and make sure you watch for any signs of stress. Good luck.”
6. Brackish tanks can be planted, too. Many people think of brackish tanks as bare aquariums due to the lack of brackish plants found in pet stores. But there certainly are some options for those who are willing to look around or purchase online. Some common ones, which survive up to 1.005 specific gravity5 include Vals, Onion Plants, Banana plants and some Crypts (ie ciliata). Above 1.005, Java Fern and Moss, Mangroves (not aquatic but can be utilized in a properly set up aquarium), and many sea grasses will survive in lower salinity tanks such as a brackish tank. For more information on Seagrasses, I recommend visiting Tom Barr and the crew at ReefCentral.com’s Marine Plants and Macroalgae Forum.
7. There are 3 main brackish habitats that often work extremely well in aquariums. To list them here would be simple, but I’d rather point you towards Schoup’s article once again, as he’s done a great job breaking down stocking, water parameters and even provides a small glimpse of each habitat.
8. Brackish ecosystems are largely consisting of small to sugarfine size substrates. The following is a picture of a mangrove lagoon underwater6:
This sandy substrate is common in most brackish ecosystems and the aquarist should attempt to recreate this by using a similar substrate. Sand has a way of compacting, and causing anoxic area (areas of low to no oxygen) which can cause all kinds of trouble for a new aquarists, so stick to a shallow 1.5’’ sandbed or less, and be sure to stir it up on occasion. Besides sand, calcium based aragonite or crush coral mixes are also acceptable and will provide some buffering for the tank, aiding in it’s stability. These substrates can also be vacuumed and easily maintained.
9. Salinity changes can be used as a positive, but no sudden shocks. In the wild, brackish systems have salinity fluctuations due to rain, tide, and flooding. These can be simulated in the aquarium, but I recommend starting with very small and gradual shifts. Avoid large shifts of more than 0.002 per day. Remember, when saltwater evaporates, the salt itself stays in the tank so brackish tanks should be topped off with freshwater only.
10. Be weary of hydrometers. Hydrometers are a useful tool, but I would not consider them to be all that reliable. After filling the hydrometer, check that there are no air bubbles inside the chamber, especially on the arm itself. Flick the unit if there are bubbles until they dislodge. Flush with warm freshwater after each use. If possible, purchase a calibration fluid to check accuracy.
This is my first article in a series known as "Good To Know" (abbr. GTK), where I will research and attempt to clarify some common mistakes, myths and fish hobby anecdotes for those who are new, and for the vets who have always wondered what information is truely correct and reliable.
The main theme of this article is answering the question of whether or not aquarium salt is the same as marine salt, and if they are different, how. Sources of information will be listed below for further reading. I would like to also reccomend that anyone interested in understanding these issues and other issues visit the Skeptical Aquarist and the AquariumWiki.
Aquarium Salt vs. Marine Salt
CONCLUSION Aquarium Salt and marine salt can both be useful but are not interchangeable in MOST instances and should be considered two completely different substances with different applications. Aquarium Salt can be used carefully, in some situations, to treat Ich or to lower Nitrite stress, while marine salt sustains marine fish, inverts and bacteria.
SUMMARY i) Aquarium Salt (there is no legal definition of this, it's an arbitrary term) and marine salt may have many similarities but the small differences completely change the useage of each product.
ii) What is often sold as "Aquarium Salt" is NaCl (Sodium choride). Marine salt is also Sodium chloride, however, marine salt is different in that it includes calcium and magnesium ions which will greatly effect the alkalinity of the water it's added to.
iii) Using "Aquarium Salt" in a reef tank will increase the NaCl levels however does not have the calcium and magnesium carbonates necesassry to sustain marine life.
iv) Using marine salt in a freshwater tank would have many of the benefits of "Aquarium Salt" but would also cause large shifts in alkalinity, PH, TDS and GH, which are fatal to most fish
v) "Aquarium Salt" has many obvious pros and cons:
PROS -The freeswimming form of Ich cannot live in water with high concentrations of salt -Restores electorlytes -Reduces "brown blood" syndrome after shipment or during times of Nitrite spikes.
CONS -Increases TDS readings; many tropical fish (see below) prefer low TDS readings especially when breeding. -If not predissolved, salt will burn fish.
vi) When deciding whether to use a simple NaCl product vs a marine salt for brackish fish, consider that many brackish organisms live in waters close to the ocean, which has a high alkalinity and GH. Thus, many of these organisms naturally operate with no osmoregualation stress in water which is higher in alkalinity and dissolved caclium and magnesium ions. Thus, marine salt is the better option as "Aquarium Salt" does not increase alkalinity or GH and doesn't provide the ideal habitat for the fish.
vii) At a certain salinity (certain dissolved substances, whereas TDS is ALL dissolved substances), which RTR states is 1.010 - 1.012, all bacteria in the tank will die and a saline-tolerant version will begin to grow. Therefor, adding marine salt at higher than those levels will cause a tank to re-cycle.
viii) Some fish can handle salt better than others - fish which live in waters with high GH, KH and PH such as African Lake Cichlids, Marine Fish, Livebearers and brackish fish will all thrive. However, amazonian fish will show signs of osmoregulatory stress if salt is added - too high levels can lead to death of fish and also to the eggs (hence why breeders take PH, GH and KH so seriously).
RESEARCH
NaCl vs. Marine Salt "What kind of salt to be using? "Salt" is the generic term for the dissolved ions and mineral component of all natural waters, which covers salts like Epsom salts, which is magnesium sulfate, characteristic of the spa waters at Epsom in England. (No, not "Epsom's" salt; "Dr. Epsom" will not be in today — or ever!) "Sea water is still better than salt crystals," Mr Innes wrote in 1935. I'd say "different" rather than "better." Sodium chloride represents only about 77% of the total dissolved solids in seawater, and marine salt's dissolved carbonates will raise your pH. When we're talking about just plain "salt" we mean NaCl, sodium chloride, which is kosher salt or rock salt ("Animal feed grade" rock salt meets high standards of purity.) "Halite" is simply a lower grade of rock salt. Impurities may color it gray or even brownish. The "halite" sold for de-icing driveways, etc. isn't pure enough for aquarium uses, as you already surmised. "Table salt" often has iodine added, not the mythic poison it's made out to be, an issue separately addressed in a few moments. Table salt often contains as well some free-running additives, like magnesium carbonate, magnesium stereate or silicon dioxide — all harmless. "Aquarium" salt is nothing but marine salt ("sea salt") that has been repackaged for the hobby and presented by colorful non-union toons in lab coats; check the label. Marine salts and Rift Lake salts contain many trace elements ("electrolytes") in addition to plain therapeutic NaCl. They are not substitutes for rock salt, nor vice versa. Nor substitutes for one another. Rift Lake waters actually contain surprisingly low concentrations of sodium chloride. As RTR pointed out, the other solutes in marine salt and Rift Lake salts will boost pH and hardness. You don't want to needlessly change those parameters as part of a medicating salt regimen." - wetman
What is aquarium salt? "There is no such thing as "Aquarium Salt". It is whatever any given manufacturer packages and labels as such. It may be routine iodized table salt, it may be unpurified and supplemented mined salt (but usually not as unsupplemented salt (NaCl) tends to fuse into a block from humidity, nobody buys such twice), or any grade of purified salt. Some is sea salt from evaporation ponds. In other words it is a pig in a poke. There is no legal definition of or for aquarium salt."- wetman
Salt and bacteria "Any salt added at and above specific gravity 1.010 -1.012 will kill FW nitrification bacteria. Smaller additions may do a partial wipe-out but not likely total unless done fast enough to osmotic shock the bacteria - which will osmotic shock the fish even quicker. If such additions are by table salt or pure NaCl, it will not support marine life of fish, inverts, and bacteria. Only marine mix (a very complex mixture of a large number of different chemicals) will do that. "Aquarium salt" will not support marine life, nor will table salt, rock salt, or sea salt."- Robert T. Ricketts
Salt and tolerance "Salt tolerance in freshwater fishes varies. The percomorph fishes, like cichlids and anabantoids, are derived from marine ancestors in the age of dinosaurs. In general, they are more salt-tolerant than ostariophysii, the loaches and minnows, characins and catfish that have descended from freshwater ancestors. Years ago, William T. Innes reported that when a range of freshwater fishes were exposed to salt baths, the first to die were Corydoras. Those ostariophysan fishes that navigate by electric fields, like knife fishes, gymnotid eels and the "elephant noses" or mormyrids, should never be exposed to salt baths, according to the University of Florida. Killifishes and livebearers are more tolerant of salt, on the whole; small tetras are less tolerant. But there are many exceptions to this very broad rule. Be aware of the salt tolerance of your particular fish."- wetman
Salt as a preventative and treatment "Salting the water to increase the mucus layer is like putting a drop of lemon juice in your dry eye to make it water. I've recently read that ammonia acts to thin and break down the slime layer of marine fish. Certainly we all know its action as a surfactant when we add a capful of household ammonia to the dishpan. If this is true in saltwater, NH3 might have a similar effect on freshwater fish. But surely you'd act to reduce ammonia levels in the water, rather than to compensate for ammonia by adding salt.
Aquarium Salt as a treatment: Salt dips and salt baths. Solutions of salt — sometimes right up to marine concentrations (35 parts per thousand) — are recommended as a short-term prophylactic bath for half an hour to remove parasites from gills, from fins and the outer surface of the epidermis, as Mr Innes recommended so long ago. Encysted parasites, like mature Ich, are less likely to be affected. Intestinal parasites aren't affected at all. Chicago's Shedd Aquarium bathes their new freshwater arrivals in full-strength seawater to rid them of ectoparasites, without losses, said a curator there in a TFHinterview a decade ago. It's smart to pass your own new arrivals through a half-hour salt bath before putting them in the quarantine tank. A five-gallon covered bucket with an aerator is what you need.
The salt concentration has to be strong enough to make gill flukes drop away. Build up your dosage with pre-dissolved Kosher salt in two or three increments and stand ready to do a 50% water change with aquarium water at the first signs of stress; heavy respiration is an early signal. You'll want to do a 50% water change anyway, when the time's up, before netting them into the QTank."- wetman
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