AQUARIUM & POND ANSWERS;
Freshwater, Marine, Sick Fish, Lighting, Baths

HITH; Hole in the Head Disease in Fish

By Carl Strohmeyer-PAMR 40+ years experience
Updated 7-2-23

I have had a lot of questions directed either to me or through the forums that I am active in about Hole in the Head Syndrome, often simply identified as HITH.
I will start off with by saying that I do NOT know everything there is to know about this disorder only to say that I have had a lot of experience in treating and controlling HITH in fish afflicted with this problem in my maintenance business over the years.

I will also note that I NEVER had an outbreak in the last 30 years of my business due to proper care of fish prone to this disorder.
In the last few decades, every case of HITH I dealt with was with a customer that called me out to help with their sick fish.
Of all the regular contract clients I had, none, and I mean NONE, EVER had a fish contract this disease. This includes large clients such as the Bahooka Restaurant with over 110 aquariums, most over 75 gallons and many with fish such as Oscars prone to this affliction.
My point as readers will find after reading this article in full, is that prevention is the key.

I state this because there is a lot of anecdotal information about HITH or even simply half truths.

What is Hole in the Head Disease?

HITH or Hexamitiasis (aka Hex) is an affliction that primarily affects Gouramis, Angelfish, Discus, Oscars and other South American cichlids.
A Cichlid has spots on their head which are called sensory pits. These are a series of fluid filled sacs with tiny hairs that sense vibrations and convert them to electrical impulses. Along the lateral lines, sensory pits are responsible for a fish's equilibrium in the water and look like little pin holes, generally arranged in a cluster.
In a HITH outbreak these sensory pits become eroded with ulcerated lesions which expand and coalesce together, forming larger crater-type lesions. They can extend deeper into the muscle and even down to the skull. These open lesions may become secondarily infected with bacteria or fungi and such secondary bacterial infections that may result in death.

A common theory is that HITH is caused by non-absorption of minerals (such as calcium) and vitamins (primarily Thiamine; Vitamin B1) from the intestine due to heavy concentrations of flagellate parasites, like Hexamita.
The importance of Calcium and other electrolytes in aquariums, ponds

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It is sometimes believed by aquarists that the protozoan parasite Hexamita caused the skin erosions and therefore treatment is based on attempting to eradicate Hexamita by treatment with Metronidazole.
This is where a half truth does come into play; Often there is a misunderstanding as stated above as to the root causes, however there is also a misunderstanding of what Metronidazole is effective against.
In this article I will not go into detail about Metronidazole other to say that it IS effective against many bacterium and parasites, especially intestinally which can effect absorption of important minerals and vitamins, WHICH IS WHY Metronidazole has been effective even when the cause was misidentified. The bottom line is Metronidazole is both anaerobic anti-bacterial AND anti-protozoal.

Please read more about Metronidazole in this article:
“How Aquarium Medications Work; Metronidazole

Product Resource: Metronidazole from AAP

As someone who sells Metronidazole and has used it, I certainly believe it has benefits, HOWEVER please let me be blunt and state again that with any suspected HITH problem, always start first with water parameters and diet, then MAYBE Metronidazole.
Quoting from a Doctor who works with refugees whom I just listened to a talk from; He noted many are trained to administer Metronidazole to refugees suffering from malnutrition, and severe dehydration resulting in life threatening diarrhea. He stated world health practices has found this to be totally wrong!
He noted that first get fluids and osmotic balance/electrolytes, and most often the patient will recover without Metronidazole and only administer Metroniazole after recovering the patient from the diarrhea.
DITTO YOUR FISH!

Back to Hexamita flagellates, these protozoans main effect as to causing HITH appears to me more indirect as this flagellate protozoan absorbs many of the nutrients in the digestive tract needed by the fish, in particular Thiamine and calcium.
So removal of these parasites with Metronidazole is certainly a worth while aspect of treatment (their presence which can be confirmed by microscopic slides), however this again is just half the problem as correcting nutrient problems is as important or possibly more important.

Thiaminase (an enzyme that metabolizes or breaks down thiamine) is also considered a problem that may be a problem in fish afflicted with HITH.
Thiaminase is introduced via feeding fish such as Goldfish/Fathead Minnows, or via bacteria. Thaimase breaks down thiamine, and thiamine is an important vitamin necessary for carbohydrate metabolism and normal neural activity.
If "feeders" (goldfish sold for the purpose of feeding other fish) are fed as a large portion of your fish’s diet, it likely will develop a thiamine deficiency.
Although many dry prepared foods contain fish flesh that also contains Thiaminase, however the process required to prepare a dry food/pellet likely destroys this enzyme.

There is not conclusive proof that this is a cause of Hole in the Head as Thiamine derivatives and Thiamine dependent enzymes are present in all cells of an animal organisms body, thus a thiamine deficiency would seem to adversely affect all of the organ systems.
However, the nervous system and the heart are particularly sensitive to thiamine deficiency, due to their high oxidative metabolism. This adds questions to this theory in my opinion.
However my own observations and limited tests certainly lead credibility to this theory.
What is also not clear is why this is more of a problem with certain fish and as well, whether the lack of Thiamine is by itself a cause of HITH. Personally I have found that with gut loading of feeders, improved mineralization and Redox that HITH ceases to be a problem even when feeder goldfish are a major part of the diet.

For a related discussion about HLLE, please see this Aquarium Answers Article:
The Lateral Line in Fish as well as Lateral Line Disease or Head and Lateral Line Erosion (HLLE)

Treatment/Prevention

This is also an area where many half truths are present (and quite honestly much is to be learned as well).
Obviously diet plays a role here, as well as water quality such as Nitrate levels, however what is sometimes missed is the role Calcium (in particular calcium cations) plays in proper osmoregulation and the fish ability to absorb other nutrients.
Often poorly maintained aquariums will see high amounts of acids, poor Redox reduction, high DOC (dissolved organic compounds), and low GH and KH (low GH or positive mineral ions). I have also noted in my service calls that the aquarist (usually with South American fish such as Discus or Oscars) was told to keep a low GH; unfortunately this is a misunderstanding of GH, Redox, and the need for calcium (even in at least small amounts in South American biotope aquariums)!

I would recommend reading this article for further information about the importance of proper Calcium levels in ALL aquariums (even Discus!):
“The Importance of Calcium, GH, KH and Electrolytes in Aquariums”

The Redox Balance (in particular lowering oxidative stress) also plays a more crucial role in prevention and treatment of HITH, as an aquarium that has a poor Redox Balance will likely never allow for recovery from HITH. Redox is directly influenced by a constant supply of mineral cations (found in part in GH), water changes, and mulm buildup.
As well, UV Sterilization has a positive affect on Redox, assuming regular changing of the UV Bulbs. To remain effective, the UV Bulb MUST be changed every six months with a premium high UVC output low pressure lamp, NOT one of the cheap ones that have only 25% of the UVC output commonly sold on eBay & Amazon for prices lower that it cost to make a low pressure HO UV bulb/Lamp.

Please see this article for more about Redox: “Aquarium Redox Potential/Balance”

Product Resource:
Premium High Output UV-C Replacement Bulb

In the end though, often a fish severely afflicted with HITH cannot be totally cured, rather the progression of this affliction can be checked.

STEPS TO TAKE FOR CURE/CONTROLLING/PREVENTION OF HITH (HEXAMITA):

• Make regular, frequent but small water changes such as 20-30% per week or even twice per week, The use of a gravel vacuum ensures better removal of decomposing wastes that add acids to the water and lower other water quality parameters such as Redox. It is also noteworthy that both Autotrophic and Heterotrophic bacteria also remove important nutrients from the water column in their life processes.


• Lower nitrates, this is important IMO as nitrate levels should be lower than 40 ppm or better, lower than 20 ppm.
  
  Please read this article about the nitrogen cycle for more nitrate information:
  "Aquarium (& Pond) Nitogen Cycle"
  More about: Nitrates


• Vary diet, avoid the use of shell fish, either avoid goldfish feeders OR feed goldfish feeders sparingly And gut load feeders with foods such as AAP Spirulina 20 or similar high vitamin and mineral foods. Feed high quality pellets or crumbles as well (or flakes if the fish will eat them).
  However since Freshwater fish do NOT drink the water around them, adding liquid vitamins to the water is not effective. Adding vitamin supplements to a fish food soak or slurry then gut loading larger fish is the best way to ensure the fish absorbs them.
  
  Unfortunately many in the hobby still believe anecdotal advice as per simply adding vitamins directly to the aquarium. HOWEVER an aquarium professional friend made an extensive study whereby the control group had no vitamins added and another group had vitamins added to the water and yet another had the vitamins added to the food.
  The result? No difference between the control group and the one with vitamins added to the water. The only improvement were with vitamins added directly to the food or simply part of natural quality fish food that is not over processed.
  Please note, many fish foods process out vitamins due to the amount of heat used, which is why besides AAP Spirulina 20, or a DEHYDRATED crumble food such as Clay Neighbor's AAP Custom Fish Food is a BETTER CHOICE.
  
  If Vitamins are to be used, a noted earlier, they are best used to soak into fish foods prior to feeding. More specifically a Vitamin B (with emphasis on B1) is really what is important for HITH.
  The best choice is AAP Vitamix Plus.
  Resource: AAP Vitamix Plus Premium Aquarium Vitamin Supplement
  
  Also as per feeding, the use of a Medicated Fish Food additive such as AAP Discomed is often very helpful and can help if there are other underlying internal bacterial and parasitic issues.
  Reference/Resources:
  *AAP Discomed (often a better choice than using Metronidazole in the aquarium)
  *Aquarium Medications; Fish Food Delivery
  
  Please read this article about fish nutrition for more about “gut loading”:
  "Fish Nutrition, Ingredients Needed for Optimum Fish Growth and Health"
  
  Further Reading:
  Do fish drink water?
  
  Quality Premium Fish Food Resources:
  *Spirulina 20 from AAP
  *Clay Neighbor's AAP Custom Premium All Natural Fish Food (optimized energy levels, proteins, fiber, & vitamins not cooked out; there is NO better prepared fish food bar NONE!)
  *AAP/Gamma Nutrashots | Fish, Corals Premium Fish Food
  
  As to gut loading feeder fish (in particular use of goldfish and Rosy Reds); many have attributed the feeding of these fish as well as frozen clams or other shell fish to a major cause of HITH due to the high Thiaminase content of these fish. I will concur with this line of thought based on many clients of mine that refused to feed anything else.
  However when mineral content of the aquarium was improved (such as using Wonder Shells), Redox was improved, AND gut loading of feeders was performed, HITH problems did not occur, even when these clients CONTINUED to feed feeder fish.
  
  Please note I am not advocating that feeder goldfish that are gut loaded be used as food, only the importance of other factors that affect HITH must be considered, as well it is noteworthy that I and many others generally note better growth of carnivores such as larger SA Cichlids (especially Piscivore Cichlids) when gut loaded feeder fish are a major part of their diet.
  
  A tablespoon of Epsom salt in a pint (16 oz.) of water can be part of a fish food soak assuming a actual but mild flagellate infestation.


• Although GH tests do not give a complete or clear picture of positive calcium ions in an aquariums, it is still a start. Increase GH to at least 100 ppm (better is 200 ppm), AAP Wonder Shells or any other method to constantly supply calcium cations along with water changes help here.
  Also make sure your carbonate hardness (KH) is at least 40-50 ppm (over 100 is often necessary for many fish)
  
  With AAP Regular Wonder Shell use, generally only 1/4 dose is required to obtain the benefit needed for a South American or similar biotope.
  
  With a known outbreak of HITH or Hexamitiasis, I strongly suggest the use of a Medicated Wonder Shell at 1/2 to full dose for even South American biotope aquarium fish. Add these along with other suggestions including food and medicated baths.
  
  Product Resource: FRESH AAP Wonder Shells (including unique versions sold nowhere else
  
  If a reliable ORP meter is available, make sure your rH reading is between 23 & 26 according to the formula found here (actually quite important):
  Aquarium Redox; Relative Hydrogen Score (rH)


• In moderate to severe cases treatment with Metronidazole may also be necessary as well as other antibiotics such as Nitrofurazone.
  In some cases of HITH, serious secondary infections occur (such as nodules around the lesions). In this case a strong synergistic antibiotic combination is called for such as the use of AAP Spectrogram
  
  Product Resources:
  FAAP Yellow Powder; Premium Nitrofurazone
  AAP Spectrogram
  Metronidazole (Metroplex from AAP/SeaChem)


• A medicated Fish Bath and/or swab can be helpful.
  In the bath, I suggest the use of Methylene Blue up to double the recommended in tank strength as per the manufacture along with Metronidazole at double strength as well.
  Epsom Salts at 1/4 teaspoon per gallon can be effective in the case of a mild flagellate infestation.
  Adding to the bath some power from scraping a Wonder Shell and liquid vitamins can also be helpful.
  Keep the fish in the bath for 20-30 minutes.
  
  As well a swab with Methylene Blue in the cap along with a about a 2-5 gallon dose worth of Metronidazole mixed into the cap (from the MB), then applied with a Q-Tip or similar directly to any pits caused by HITH.
  
  Further Information of Fish Baths & Swabs (recommended reading!):
  Fish Baths, Dips, & Swabs
  
  Product Resource: Methylene Blue from AAP
  
  Outside Resource: The Krib; Diseases of Apistos


• Finally a clean WELL filtered aquarium is a MUST

Other Recommended Reference & Product Sites

Aquarium Information
The largest data base of aquarium information available on the Web.

Fish Treatments, How They Work, Which to Use and Not to Use

Freshwater Aquarium Information; Basics to Advanced

FISH AS PETS
Fish as Pets with articles & commentary of Interest to the Aquarium Hobby

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Labels: Cichlid Disease, Fish Calcium Deficiency, Head Syndrome, HITH, HITH Disease, Hole in the Head, Metronidazole, Oscar Disease

By Carl Strohmeyer-PAMR 40+ years experience
Updated 11/1/21

The Lateral Line in Fish as well as Lateral Line Disease or Head and Lateral Line Erosion (HLLE)

The lateral line is a sense organ that consists of a row of scales that most fish have along their sides, extending from their head to tail. Under these scales are a system of fluid-filled canals and specialized cells which transmit vibrations to the brain of the fish.
The lateral line helps fish to detect movement and vibration in the surrounding water including predators and prey. The lateral line or similar organs in fish such as blind cavefish (which has rows of neuromasts on their heads) are used precisely to locate food without the use of sight.
Killifish can sense ripples caused by insects struggling on the surface of the water.
Scientific experiments with Pollack Fish have shown that the lateral line is also used for schooling behavior.

IDENTIFICATION:

Lateral lines are usually visible as faint lines running lengthwise down each side, from the area around the gill covers to the area near the base of the tail. Sometimes parts of the lateral line are modified into electro-receptors (biological ability to receive and make use of electrical impulses), which are organs used to detect electrical impulses.

HISTORY:

A Scientist in the 1960s named Sven Dijkgraaf argued convincingly that fish must use their lateral lines to detect water motion. This motion can be generated by the fish, water currents, or by some external moving object.
The lateral line in fish seems to have the ability of detecting the subtle movements of biological sources (prey fish or predator fish, for example) located some distance away. Many scientists believe that fish such as sharks can use these organs to detect magnetic fields as well.

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HOW THE LATERAL LINE WORKS:

There are receptors in the line, called neuromasts, each consist of a group of hair cells, these cell hairs are surrounded by a protruding cupula (an organ that gives an animal a sense of balance).
Neuromasts may occur singly, in small groups called pit organs, or in rows within grooves or canals, where by these neuromasts are referred to as the lateral line system.

The lateral line system runs along the sides of the body onto the head, where it divides into three branches, two to the snout and one to the lower jaw.
These neuromasts are usually at the bottom of a pit or groove in the fish, which is large enough to be visible.

Skates, rays and sharks usually have lateral-line canals, in which the neuromasts are not directly exposed to the environment, but communicate with it via canal pores.
The hair cells in the lateral line are similar to the hair cells inside the others vertebrates inner ear (such as the cupula in humans where hair cells within the cupula sense rotational acceleration), indicating that the lateral line and the inner ear share a common origin.
Some active fish that are constantly swimming tend to have more neuromasts in canals than on the surface, and the lateral line will be further away from pectoral fins, to reduce the noise generated by fin motion.

The lateral line system, found in many fish, is sensitive to differences in water pressure. These differences are thought to be due to changes in depth or to the current like waves caused by approaching objects.
When pressure waves cause the gelatinous caps of the neuromasts to move, bending the enclosed hairs, the frequency of the nerve impulses is either increased or decreased, depending on the direction of bending.

A swimming fish sets up a pressure wave in the water that is detectable by the lateral line systems of other fish. It also sets up a bow wave in front of itself, the pressure of which is higher than that of the wave flow along its sides.

These near-field differences are registered by its own lateral line system.
As the fish approach an object, such as a rock or the glass wall of an aquarium, the pressure waves around its body are distorted, and these changes are quickly detected by the lateral line system, enabling the fish to turn or to take other actions.
Because sound waves are waves of pressure, the lateral line system is also able to detect very low-frequency sounds of about 100 Hz or less.

An adaptation of the pressure-sensitive system is seen in the modified groups of neuromasts called the Ampullae of Lorenzini (special sensing organs, forming a network of jelly-filled canals), which are found in sharks, rays and a few bony fish.
The Ampullae of Lorenzini are able to detect electrical charges, or fields, in the water.

Most animals, including humans, emit a DC (Direct Current) field when in seawater. This is thought to be caused by electrical potential differences between body fluids and seawater and between different parts of the body. An AC field is also set up by muscular contractions.
A wound, even a scratch, can alter these electrical fields.

DISEASES OF THE LATERAL LINE:

Often the lateral line in fish, marine in particular will get infections or degenerate from water conditions. Many believe Marine Head and Lateral Line Erosion is related to Hole in the Head (HITH).

The usual progression in marine fish of MHLLE (Marine Head and Lateral Line Erosion) is usually the development of small pits around the eye and on the head and adjacent area.
As the ailment progresses, the holes grow larger, eventually connecting to become larger lesions, eventually extending back along the fish's lateral line. The fins and gill covering will also often erode in more advanced cases, although MHLLE is seldom fatal.
Yellow Tangs for an unknown reason progress differently; they tend to lose their vibrancy and lighten in overall color, followed fin erosion, usually beginning with the soft tissue between the dorsal fin's rays.
In general Marine Angels and Tangs (Surgeonfish) seem to be the most susceptible to MHLLE.

THEORIZED CAUSES

Vitamin, Immune System

Vitamin and mineral deficiencies such as Vitamin C and possibly Vitamin B complex are one very likely cause of degeneration from my experience.
Proper feeding of foods high in these vitamins such as Spirulina Algae will help in this case.
These deficiencies along with poor water quality (which often results in poor Redox balance) show the most evidence for being the major cause of this affliction.

More information about: Aquarium Redox

Recommended Fish Food Resources:
  -Spirulina Algae Fish Food Flake
  -AAP Custom Fish Food Crumbles by Fish Food Guru Clay Neighbors

Many have attributed high nitrates due to poor water quality as a possible cause, however although low nitrates are certainly important for long term health, I believe high nitrates play a minor role in how poor water affects HLLE in fish.
I believe from my own tests (as well as research) that the lack of minerals and vitamins in low quality water along with a poor Redox Potential are the main culprits. I have witnessed Yellow Tangs turn around with the addition of trace elements in client’s tanks that previously never supplemented them.

As stated earlier the use of products such as Spirulina Algae, high quality additives such as SeaChem Vitality (as a fish food soak), adding trace elements & complete buffers as well a simple and basic water changes using quality salts aids profoundly in maintaining proper mineral/vitamin levels in marine fish. This is especially important since marine fish constantly drink the water around them which makes their body chemistry very much like that of the water around them (somewhat of an over simplification though).
Also for finicky marine fish such as many Butterflies and Angels, the use of products that entice the fish to eat high quality prepared fish food that they might otherwise ignore is suggested; one excellent example is SeaChem Entice

A Great Resource for more about Marine Fish & how they drink water:
Aquarium Answers, Do fish drink water?

Aquarium Redox & rH

Another aspect of water quality, immune system health is the The Aquarium Redox Potential.
A basic explanation; simply put a correct Redox potential acts as an anti-oxidant clearing away free radicals much the way many vitamins such as A, C and others do. Many aquarists are unfortunately unaware of this aspect of the aquarium keeping even though many human studies have shown direct correlation to correct Redox and lowering of free radicals.

More in depth though is the potential affect of Redox as it relates to electromagnetism and rH (relative hydrogen). While this is still in the arena of theory, my personal observations lead credibility to this, and in fact both science and observation make oxidative stress the leading factor in HLLE in my opinion!!
Early results suggest healthy aquariums will have rH reading s between 23 & 26

PLEASE reference this article for more on this subject:
“The Aquarium Redox Potential”.
Also Reference:
UV Sterilizer use for Redox Balance

Stray Electrical Current

Another theory is that an un-grounded aquarium can cause electrical fields that both interfere and degenerate the lateral line in fish. You can test this by using a pocket multi-meter on AC volts with a probe in the wall ground and a probe in the water.

HOWEVER, newer evidence does not seem to support this theory which quite bluntly from my experience makes sense as I have witnessed many broken or leaking electrical devices over years that I can actually feel the “stray” electrical current by holding my hand just above the water or if I have an open cut, YET the fish do not seem to be affected UNTIL one completes the circuit. An example is a Pacu I witnessed that “bit” into a loose set of wires that a client had left hanging into the tank, all was fine until the fish “completed” the circuit.
My point is that there is NO completed circuit until you complete it with a ground, which you do when touching the water while standing on the ground.

Carbon and NPOC

Other HLLE theories include the use of activated carbon, however in admittedly non-controlled studies I have seen no difference in occurrence or cure with the use of carbon, however it is possible that many are not keeping up with trace elements, and have a poor Redox and then the addition of carbon might remove what little anti-oxidants there are in an aquarium, but I do not think one can safely state that the use of carbon will lead to HLLE.

Another aspect of carbon that is not really related to the above use of activaed carbon is "Total Organic Carbon" ( aka TOC). This the amount of carbon found in an organic compound and is often used as a non-specific indicator of water quality. A general analysis for "Total Organic Carbon" measures both the total carbon present and the so-called "inorganic carbon", the latter representing the content of dissolved carbon dioxide and carbonic acid salts. Subtracting the inorganic carbon from the total carbon yields TOC.
Another common variant of TOC analysis involves removing the IC portion first and then measuring the leftover carbon. This method involves purging an acidified sample with carbon-free air or nitrogen prior to measurement, and so is more accurately called non-purgeable organic carbon (aka NPOC)

Referenced from:
Total organic carbon; Wikipedia

This clearly may have a bearing on Redox and rH, thus this theory has merit in it based on my research and experience, however no confirmed scientific studies have confirmed this as a causative factor in HLLE.

Use of Ozonizers/Ozone Generators

Both my observations and those of others confirm that the use of an aquarium Ozone Generator is a factor in MHLLE disease.
I have observed on multiple occasions that HLLE will get worse when the Ozonizer is added and improve when the Ozonizer is removed.
This said, removal has not cured HLLE either, so it is only a factor in my experience.

Better to use a high dwell time UV Sterilizer such as the AAP/TMC Vecton models for germicidal use and only use the Ozone Generator for improving protein skimming ina protein skimmer designed to handle an Ozonizer such as the AAP V2 Skim Marine Skimmers.

Product Resources:
*AAP Vecton/Advantage High Dwell Time UV Sterilizer
*AAP V2 Skim Professional Venturi Marine Aquarium Skimmers

Viruses, bacteria and parasites

Viruses, bacteria and parasites have also been blamed and once again I have not seen enough supporting evidence to support this theory as well.

Copper

Exposure to Copper is another theory, however once again since I used to use copper extensively over the years and have not observed any such correlation with normal use. This said, I would concur with this theory when copper levels exceed normal doses for long periods of time. I would suggest the use of Ionic Copper and not Chelated Copper.
Product Resource: AAP/SeaChem Ionic Copper

Lighting

Finally another theory that does make sense based on my experience with 100s of marine aquariums (although not scientifically proven) are the lack of sunlight or correct lighting.
Proper lighting (or lack thereof) is another parameter for a healthy lateral line in fish.
Full spectrum lighting such as a combination 6,400 K or 20,000 K bulb and Actinic (UVA) bulb will help with this. The thought is that full spectrum lighting aids in the assimilation of certain vitamins, much as in humans and Vitamin D.

Please reference this very in depth article:
Proper Aquarium Lighting

Theory Summary

The subject of HLLE is something unlike other fish maladies, even HITH in freshwater fish, where I have made certain changes and never had a reoccurrence of the issue.
So while I have good evidence, both science and experience based, I cannot state categorically what the exact cause and preventative actions are for HLLE.

My best guesses based on this experience and research is that nutrients/vitamins, Redox/rH, & lighting are the key factors to focus on.

Further Reference:
* The Krib- Lateral Line Disease

Other Recommended Reference & Product Sites

AQUARIUM AND POND INFORMATION;
Well researched and up to date aquarium and pond answers, help, and links. Based on 35 years of professional aquarium maintenance experience.


Fish Diseases | How to Treat Sick Fish


Saltwater/Reef Aquarium Basics

*Aquarium Chemistry; Saltwater & Freshwater

*Fish Nutrition Information

*Marine Oodinium

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Labels: HLLE, Hole in the Head, Lateral Line, Lateral Line Disease, Marine Fish, MHLLE, saltwater, sick fish