Fish Health Diagnostics (Read before posting.)

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Registered Member
Sep 21, 2006
Lupin Information Super Highway/Goldfish Informati
Real Name
Basic Questions

1. What is the size of your tank?

State the tank volume in liters or gallons. If you are unsure of your tank size, use this calculator to determine the tank size.

2. What are your water parameters? State the brand of test kit used.

This question is frequently evaded by people whenever they ask help for fish health issues. Failing to post the water parameters will not give you proper diagnosis of your fish. It s very important you monitor your ammonia, nitrite, nitrate, pH, KH (carbonate hardness) and GH (general hardness). Ammonia and nitrite are both toxic substances with the former being more toxic on the alkaline side (> 7.0). Both substances must remain in zero levels to avoid intoxication among the fish.

Nitrate generally is a harmless substance provided it does not exceed 40 ppm. More than 40 ppm poses a greater risk to the fish particularly stunting of the fish's growth and increased susceptibility of the fish to health issues.

pH varies depending on the fish and their ability to adapt to the changes in their surroundings. It is easily influenced by the buffering capacity of the KH and GH. KH itself always play a bigger role in the fish's ability to adapt compared to the pH as KH helps with the stability of pH depending on the variables that may influence the changes.

For test kits, a set of Aquarium Pharmaceuticals (API for brevity from hereon) liquid test kits is widely recommended. Test strips are not entirely reliable for accuracy and validity.

3. Is your aquarium set up freshwater or brackish water?

Saltwater will not be included here as it has its own forum for this purpose. It is common belief that merely adding "aquarium" salt or table salt already makes the tank brackish water. This is absolutely incorrect. Neither of the two carry properties required to replicate the brackish water environment. Marine salt is recommended for this case. When you measure your salinity, get a hydrometer or refractometer. Make sure your measurements are accurate.

4. How long the aquarium has been set up?

We often think a week establishment of the tank after finishing the cycling phase already means the tank is well established. This is a common fallacy especially as the bacteria have not colonized well enough so you have to expect ammonia and nitrite to sometimes go up to dangerous levels. In this case, a water change has to be performed to keep them to safe levels.

5. What fish do you have? How many are in your tank? How big are they? How long have you had them?

This is another question often not answered. Compatibility is the most common issue especially as beginners have the tendency to buy their fish on impulse without doing any thorough research first and then cramping their tanks afterwards thinking it is okay to keep it that way. Overcrowded tanks increase the fish's susceptibility to various diseases often from ich outbreaks to viral outbreaks.

Aggression breaks out as a result of lack of space and hiding places. Eventually the victims are weakened by constant harassments and may die from starvation in the process as a result of fear of further harassments. Bullied specimens tend to shy away and may be unable to get their fair share of food in order to survive. In this case, either the aggressor or its victim must be removed. Rearranging the decorations may help although in most cases, it only worsens the aggression issue. Adding more hiding places enables the victim to hide thus avoiding further damage. This is one of the few main reasons why patience is an important virtue in this hobby. You must thoroughly research the fish you want and always be prepared if you want to avoid future problems.

6. Were the fish placed under quarantine period (minus the first batch from the point wherein the tank is ready to accommodate the inhabitants)?

Usually, with the first batch of stocks, we do not need to quarantine the fish as there is nothing else that may be infected by pathogens other than the first inhabitants themselves however in several cases, people assume, regardless of their resources, their fish are in perfect health conditions. They fail to realize even healthy specimens themselves can be disease carriers and eventually end up destroying even their current stocks from failure to quarantine the new arrivals.

It is always recommended to quarantine your new arrivals regardless of the circumstances. The choice is yours. If you prefer to protect your current stocks, then prepare a quarantine tank no less than five gallons in tank volume. Make sure the tank has ample space with a few decorations for the fish to seek refuge, heater and sponge filter. The tank does not need to have substrate for hygienic reasons. A quarantine tank itself is doable in the long run and can be run as a hospital tank or isolation tank (for aggressors). A minimum of four weeks is the suggested time frame when quarantining your stocks. It gives ample tank for the pathogens to set in thus enabling you to prevent them infiltrating your main tank and destroying the stocks in it.

7. What temperature is the tank water currently?

A lot of fish depend on the temperature just like the water parameters n order to thrive. Most specimens lack tolerance for warm temperature (> 26 degrees Celsius) or cold temperature (< 24 degrees Celsius). The temperature must therefore be adjusted to ensure the fish you want, thrives for a long time.

Generally, in warm environments, the oxygen dramatically reduces. This is where surface agitation is very important. When the temperature has to be maintained at a specific level, you must ensure the oxygen supply is adequate. It is widely encouraged to use airpumps regardless of the circumstances although in most cases, the sponge filter itself (or any other filters that create surface turbulence) is already doable so the airpump may not be necessary at all.

Note: Battery airpumps are a must in areas where power outages are quite frequent. A sponge filter attached to the airpump makes it very efficient in this case.

8. Are there live plants in the aquarium?

Live plants have the potential to introduce pathogens that may have adverse effects to your fish's health. There are also cases involving harmful bugs such as water boatmen, dragonfly nymph and fish lice that are introduced to the tank and then wreak havoc to your current stocks. It is highly advisable that the plants be quarantined or dipped in potassium permanganate, 10% bleach solution or malachite green. All three chemicals can destroy a lot of parasites that may harbor in the plants.

9. What filter are you using? State brand, maintenance routine and power capacity.

Inadequate filtration often is a result of poorly maintained tanks. Detritus and other waste materials are not picked up by the filter or movements therefore leaving dead areas where the anaerobic bacteria begin to colonize thus creating hydrogen sulfide which if disturbed, can cause acute respiratory problems among the fish and other aquatic creatures.

There are brands of filter that fail to work to the standards despite their claim. This must be double checked to make sure your filtration capacity can cope with the amount of wastes excreted by your tank stocks.

Clogged filters must also be cleaned regularly as they block the flow thus the bacteria are unable to work through the nitrogen cycle process leading to disastrous consequences. Never use hot water or detergents to clean your filter and its filter media. This will destroy the beneficial bacteria responsible for the nitrogen cycle which enables the fish to live in a healthy environment. Always use the tank water or dechlorinated tap water when doing so.

10. Any other equipment used (aside from heater and filter which are two very important components of the tank)?

This will include sumps, DIY CO2, pressurized CO2, diatom filters and anything else that does not fit the basic category.

11. Does your aquarium receive natural sunlight at any given part of the day? What is your lighting schedule (assuming you do not rely on sunlight for our viewing pleasure)?

Excessive sunlight (or artificial lighting) can lead to algal blooms assuming phosphates and nitrate are high. This is often caused by overdosage of plant fertilizers, overfeeding where foods contain to much phosphates as is the case with most brands and failure of plants to outcompete the algae for food due to insufficient number of plants thereof.

12. When did you perform your last water change and how much water was changed? How often do you change your water? Do you vacuum the substrate?

Any sudden changes in the water parameters caused by large infrequent water changes can hinder the fish’s ability to adapt in its environment. This will cause severe stress on the part of the fish. Many people blame large water changes for their failure to keep the fish alive but what they fail to realize is their inability to do large water changes consistently is often the main cause of their failure. If the tank has been neglected for quite some time, it is recommended to start with small water changes daily until you can reach the point when you can begin performing your usual large water changes to avoid the fish from being shocked by the changes in its environment. Your routine varies greatly in the amount of wastes excreted by your fish, feeding routine and filtration capacity.

13. What foods do you provide your fish? What is the feeding schedule?

Fish in the wild do not get as much food as fish in captivity do. This is influenced greatly by the climate changes. A prime example would be the lifestyle in Amazon river. During droughts, the rivers lessen in space thus lessening the territorial needs of the fish and even food supply. Fish fight in order to survive whereas during rainy seasons, the rivers overflow and cover a wide forest floor area thus enabling the fish to establish their territories and breed with the food supply in great abundance. In captivity however, fish do not need to do anything in order to survive. The owner is there as the provider but most of us sometimes become overly generous that the fish looks abnormally bloated.

A fat fish is not a healthy fish. This in itself goes without saying. A fat fish tends to have more health problems compared to a fish that is fed less. Why? Constipation, internal organ prolapsed and bloating are common serious digestive issues that may influence the lifespan of the fish as it attempts to balance its organ functioning. Once the food accumulates in its body system and cannot be expelled, this may cause the organs to malfunction and the fish dies in the process. This is often the case with overly fed fish.

Another issue of overfeeding is the food simply accumulates to the bottom and decomposes. This can cause the ammonia and nitrite to rise dangerously and may cause intoxication of the fish. Always vacuum the leftover foods after five minutes of feeding. Do not rely on your “scavengers” to do the job for you.

Fish also get different kinds of vitamins and minerals when they are fed with various kinds of foods. Sticking to one as a staple is not healthy as the fish cannot get the vitamins it needs. It is very important to note that the fish must also be fed appropriately. In this case, you must make sure the food does not pose a health risk to a certain type of fish. For example, mbunas are primarily vegetarians. There is no excuse in feeding them meaty foods such as bloodworms because they “appear too eat them quite enthusiastically”. Animal protein is far different from plant protein. The former is very hard to digest and in excess, this can accumulate in the body organs and failing to expel the proteins may cause the fish to suffer dropsy or “Malawi bloat”. This is not very easy to correct and in most cases, the fish eventually dies. Note that vegetarians have longer intestines compared to carnivores so it will make sense that the proteins will take a long time to be totally expelled or digested.

14. What unusual signs have you observed in your fish?

It is common practice that we monitor the health of our fish daily and this is easily determined when you are doing your rounds of feeding. When a fish fails to appear during feeding time as it normally would, this needs your attention. You must determine what went wrong with the fish. Does the fish look thin? Is it moving listlessly? Does the appearance of its wastes look unusual? Are the fins clamped at all? Signs like this should be taken seriously. The suspected fish must be isolated immediately before any possible disease outbreak may occur which can damage a lot of your stocks.

If the fish is not found at all or simply disappeared mysteriously, check all your decorations and equipments thoroughly. Failing that, check the fish during the night with a flashlight and see if it comes out of hiding. If the fish is suspected to have died, get your test kits and run in your ammonia, nitrite and nitrate. If the ammonia is unusually high, then a water change needs to be in order and monitor your other fish for any unusual behavior.

15. Have you treated your fish ahead of diagnosis? If so, what treatments did you use? State your reasons for planning ahead of proper diagnosis.

It is easy for us to "dump" chemicals recklessly thinking what we are doing, is in proper order. This is not advisable nor is it encouraged. When you treat your fish with a chemical assuming the fish has what you think it really has without considering other variables first, you are simply doing more harm than help the fish at all. Many chemicals are fatal to the fish, let alone the invertebrates. Most chemicals are suggested in half dosage due to their potency. Always use caution when treating your fish.

If in doubt what to do, be sure to post complete details by using the above questions so the other hobbyists may be able to diagnosis your fish properly thus enabling you to save your fish in due time. Never resort to adding chemicals unless you know what you are doing.

Mixing chemicals is also another reckless way. Some chemicals develop a reaction which can prove more potent than the pure chemical can. When dealing with mixed infections, always ask for more opinions or ask your fish veterinarian before you spring into action to save your fish. It is important you focus on eradicating the more dangerous infection first before moving on to another to avoid the fish from coping with too much stress from the chemical switchover in your attempt to eradicate both infections at the same time. A safer option would be to pick the medicine that can eradicate both infections safely and efficiently.

Common Causes of Unusual Behaviors
This will cover common ailments only. The more complicated health conditions can be found here.

1. Fish is scratching more than usual.
-This could be ich, bacterial infection of the skin, gill flukes, skin flukes and external parasites such as fish lice (Argulus sp.). Refer to this.
-Injuries. Keep water clean to allow injuries to heal.
-Silt irritation. Use filter floss to flush out the fine particles responsible for irritation.
-Fiber glass attached to plant roots. Fiber glass can cause irritations even to human skin. Remove the material.

2. Unusually tattered fins or fins with punch holes.
-Deteriorating water conditions. Check your water parameters and correct wherever necessary.
-Aggression. Correct the aggression issues and consider isolating the aggressor if things do not improve.
-Sharp decorations. Replace the decorations with sharp edges.
-Exposed filter outlet of the powerhead.

3. Faded or unusually dark body color.
-Deteriorating water conditions associated with ammonia and nitrite intoxication. Refer to #2.
-Improper acclimation procedure. Compare your water parameters with your source and correct it.
-Stressful activities. This will include high traffic areas where people keep passing by, bright lighting, boisterous activities of tankmates and unnecessary disturbances around the tank.

4. Unusual patches on the body.
-Fungal infection (saprolegnia). This is very rare. For further information, check here.
-Bacterial infection. An infection more common than most people anticipate and often mistaken for fungal infection. For further information, check here.
-Skin infection. This will comprise of trichodina, costia, tetrahymena, etc.
-Infected wounds or injuries. Use mercurochrome as a topical treatment here.
-Fish tuberculosis.

5. Graze marks.
-Sharp decorations. Refer to #2.
-Aggression issues. Refer to #2.

6. Cysts, craters or spots.
-White spot or ich, oodinium, bacterial infection. Go here.
-Lymphocystis or viral disease.
-Tumor (whether benign or cancerous). Euthanasia is the last option if the fish has a rather slim chance of recovery otherwise the tumor can be removed surgically.
-Vitamin deficiency for craters or hole in the head/lateral line erosion.
-Internal parasites for craters.

7. Unusual bloating.
-Dietary issues. Post your food menu and guaranteed analysis (ie. crude fiber and crude protein percentage).
-Deteriorating water conditions. Refer to #2.
-Internal parasites. Refer to this.
-Improper acclimation procedure. Refer to #3.

8. Protruding eyes and scales.
-Deteriorating water conditions. Refer to #2.
-Internal parasites. Refer to #7.
-Injuries. Refer to #1.

9. Gasping and listless movements.
-Deteriorating water conditions. See #1.
-Oxygen deficiency. Raise surface agitation using airpumps or increase the power of the powerheads and filters to create surface turbulence.
-Fish tuberculosis.
-Lack of tolerance for high temperature.
-Improper acclimation procedure. See #3.

10. Red veins.
-Hemorrhagic septicemia.
-Deteriorating water conditions. See #2.

11. Refusal to eat.
-Internal parasites. See #7.
-Deteriorating water conditions. See #2.
-Inappropriate treatments. Stop using treatments for a few days and repeat with a new brand (making sure diagnosis is correct).
-Improper acclimation procedure. See #3.
-Stressful activities. See #3
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Registered Member
Sep 21, 2006
Lupin Information Super Highway/Goldfish Informati
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Folks, please be reminded that we appreciate longer informative posts than short essays that still have very vague details. This makes a faster diagnosis than to keep assuming what the cause is and potentially harming the fish in the process. If at all possible, take your time to read this diagnosis thread and copy and paste the questions. Answer each question when you make a thread about your fish's health issues.

Bumping threads:

If you wish to bump your thread, please do this once a day only. Do not bump more than once unnecessarily. Help will get there in time. If it helps, add the word "emergency" on the thread title so others can quickly read through your problems.

Shorter Version of Diagnostics Form:
1. Size of tank?

2. a. Ammonia?
b. Nitrite?
c. Nitrate?
d. pH, KH and GH?

3. Temperature?

4. FW (fresh water) or BW (brackish)?

5. How long the aquarium has been set up?

6. What fish do you have? How many are in your tank? How big are they? How long have you had them?

7. Were the fish placed under quarantine period (minus the first batch from the point wherein the tank is ready to accommodate the inhabitants)?

8. a. Any live plants? Fake plants?
b. Sand, gravel, barebottom?
c. Rocks, woods, fancy decors? Any hollow decors?

9. a. Filtration?
b. Heater?

10. a. Lighting schedule? What lights are used?
b. Any sunlight exposure? How long?

11. a. Water change schedule?
b. Volume of water changed?
c. Frequency of gravel/sand (if any) vacuumed?

12. Foods?
How often are they fed?

13. a. Any abnormal signs/symptoms?
b. Appearance of poop?
c. Appearance of gills?

14. a. Have you treated your fish ahead of diagnosis?
b. What meds were used?

15. Insert photos of fish in question and full tank shot if necessary.
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