This is your completely guide to dropeye(DE). MOST questions about DE will be answered here, but I'm sure there are many more. If there is a question that isnt covered here, feel free to ask as it might be important.
Outline
1. Explanation on DE and so called "cures".
2. First will be an order from greatest chance to least chance of getting DE.
3. Second will be the myths on what causes DE.
4. Third will be contradictions within each myth.
5. Fourth will be what makes sense in each myth.
What Is Drop Eye and How Can You Prevent It?
To start off I want to state dropeye, is NOT a disease or a sickness, it will not be spread and it will not be caught. Dropeye is very self explanatory, its when an arowana's eye(s) are looking down. Some aros get very light DE where the eye is slightly angled down, while there are some very extreme cases where the eye looks as if it will fall out at any given second.
There are currently nothing that can prevent or cure DE at the moment. THe only "cure" is to put your arowana in a huge pond, but this has not been proven and may not work as wild arowanas have DE too. It has also been said that floating ping pong balls in your tank will solve DE as your arowana will look up at it. Your arowana will give it 10 seconds of interest and go back to doing what it always does. It might even be hazardous if you have a big arowana that can swallow the ping pong ball. To put it short, there are NO proven cures as of now.
Which Aro Is Most Prone?
Silver Arowana- When you say DE, the first arowana that people think of is the silver arowana. There has yet to be a picture of a silver arowana without DE over 20". DE usually starts developing after the aro hits 16".
Jardini/Leichardti Arowana- Jardinis and leichardtis are both aussie arowanas, they are NOT the same, but will be grouped the same for this. Jars/leis do not develop DE as common as silvers, but the majority of them do after hitting 16"-18".
Asian Arowana- The asian arowana has a very low chance of getting DE. Though it is not common, it does not mean they cannot get it. Usually, DE is only found on the bigger asian aros (24"), and rarely, if ever, found on a smaller aro.
African Arowana- The african arowana is not a true arowana but will be included into this. African arowanas cannot or will rarely ever get DE. There has yet to be a photograph of an african arowana with DE (on mfk and google of course).
Black Arowanas- Like the african arowana, the black arowana cannot or will rarely ever get DE. There is also no photographs of black arowanas with DE.
*May not be relevant with DE, but it is still worth mentioning. Arowanas slow their growth rate when they reach the 16"-18" mark, this is exactly the same time that DE starts to develop in most arowanas. Are these 2 events connected somehow?*
What Causes DE?
So heres the important question, if there are no cures for it, then what causes it? There is no definite proof yet to answer this question. We still have no idea what cuases DE but we do have many theories. Below is a list of the most common myths and beliefs on how DE is formed. There is probably many more, but there are too many, thus only the most common ones will be listed.
(I will refer to each belief by number after listing them)
Beliefs:
1. DE caused from excess fat
2. DE caused from head trauma*
3. DE from tank reflection
4. DE from strong light
5. DE from looking down
6. DE from genetics
Meaning:
1. DE is caused by an arowana eating too many fatty foods like feeder goldfish. The fat builds up behind the eye and pushes it down, causing DE.
2. DE is caused by an arowana hitting the tank sides too hard. The trauma or shock from it losens the eye from its socket and the aro develops DE.
3. DE is caused by the tank reflecting light. The light reflects into the arowana's eyes and cuases DE.
4. DE is caused by strong lights. The arowana is bothered by the light, thus it has to look in a different direction and the eyes look down and DE develops.
5. DE is caused by an arowana looking down. No matter the cause, whether it be becuase of light or becuase it is looking for food, when it looks down, it starts to get used to it and eventually becomes permanent thus having DE.
6. DE is caused by genetics.
What Doesn't Makes Sense?
1. If DE is caused by fatty foods, then why do only some aros get it? Why can't we prevent DE by feeding lean foods if it is caused by excess fat buildup? Why don't blacks or africans get DE even if you gutload them with feeders?
2. If DE is caused by head trauma, why would asian aros be less prone to get it than silvers? Why would they have DE in the wild if there is really nothing for them to ram their head into in the wild?
3. If DE is caused by light reflections going into the eye, then why can't it be cured by simply turning off all the lights and not letting any light get to the arowana?
4. If DE is caused by the arowana looking in a different direction due to lights, why can't we just cure it by turn off all lights and wrapping the tank in black?
5. If an arowana gets DE by looking down, why can't we just take away all factors that make it look down?
6. If DE is caused by genetics, what makes almost all, if not all, silvers get DE while only a selected number of asian arowanas able to get DE?
What Makes Sense?
1. When you think about it, when humans gain weight, they get bigger and bulkier. If an arowana worked the same way, there could be fat build up behind the eyes thus pushing it out.
2. We always see it in the movies, someone gets hit in the back of the head, and their eyes come popping out, this can also apply with an arowana when the arowana rams into the tank glass. This would also explain why silvers and aussies are more prone to get it than asian arowanas. Silvers and aussies are very jumpy and skittish arowanas, they will dart when they get scared (which is very often) and is not surprising if it hits the tank glass while asian arowanas are more calm and will not be scared as easily, thus explaining while asian arowanas are less prone to DE. African arowanas are also the calmest out of all arowanas, which would mean it would rarely dart into the glass, thus, rarely ever having head trauma.
3. Lights are harmful, especially to the naked eye. If human eyes can be hurt by light, arowanas might also be the same.
4. It is basic reaction that when something is shot at your eye, you either block your eyes from it, or you move your eyes elsewhere. Arowanas have nothing that can shield their eyes, thus they would need to look elsewhere.
5. Humans have habits, so do fish. If we start to slouch for a long period of time, we will be accustommed to it, same can be said for an arowana looking down.
6. Genetics would explain why silvers are very prone to DE while blacks are virtually immune to it even though they are both very similar. This would also prove why you cannot prevent or cure it.
*Special Point* Have you noticed the asterisk on point number 2? The theory that head trauma causes DE is the ONLY theory that has been proven, not just by one but by many people. Bderick67 is one of those people who have personally witnessed his own silver arowana develop DE in just a mere 30 minutes right after it jumped out and hit its head.
Outline
1. Explanation on DE and so called "cures".
2. First will be an order from greatest chance to least chance of getting DE.
3. Second will be the myths on what causes DE.
4. Third will be contradictions within each myth.
5. Fourth will be what makes sense in each myth.
What Is Drop Eye and How Can You Prevent It?
To start off I want to state dropeye, is NOT a disease or a sickness, it will not be spread and it will not be caught. Dropeye is very self explanatory, its when an arowana's eye(s) are looking down. Some aros get very light DE where the eye is slightly angled down, while there are some very extreme cases where the eye looks as if it will fall out at any given second.
There are currently nothing that can prevent or cure DE at the moment. THe only "cure" is to put your arowana in a huge pond, but this has not been proven and may not work as wild arowanas have DE too. It has also been said that floating ping pong balls in your tank will solve DE as your arowana will look up at it. Your arowana will give it 10 seconds of interest and go back to doing what it always does. It might even be hazardous if you have a big arowana that can swallow the ping pong ball. To put it short, there are NO proven cures as of now.
Which Aro Is Most Prone?
Silver Arowana- When you say DE, the first arowana that people think of is the silver arowana. There has yet to be a picture of a silver arowana without DE over 20". DE usually starts developing after the aro hits 16".
Jardini/Leichardti Arowana- Jardinis and leichardtis are both aussie arowanas, they are NOT the same, but will be grouped the same for this. Jars/leis do not develop DE as common as silvers, but the majority of them do after hitting 16"-18".
Asian Arowana- The asian arowana has a very low chance of getting DE. Though it is not common, it does not mean they cannot get it. Usually, DE is only found on the bigger asian aros (24"), and rarely, if ever, found on a smaller aro.
African Arowana- The african arowana is not a true arowana but will be included into this. African arowanas cannot or will rarely ever get DE. There has yet to be a photograph of an african arowana with DE (on mfk and google of course).
Black Arowanas- Like the african arowana, the black arowana cannot or will rarely ever get DE. There is also no photographs of black arowanas with DE.
*May not be relevant with DE, but it is still worth mentioning. Arowanas slow their growth rate when they reach the 16"-18" mark, this is exactly the same time that DE starts to develop in most arowanas. Are these 2 events connected somehow?*
What Causes DE?
So heres the important question, if there are no cures for it, then what causes it? There is no definite proof yet to answer this question. We still have no idea what cuases DE but we do have many theories. Below is a list of the most common myths and beliefs on how DE is formed. There is probably many more, but there are too many, thus only the most common ones will be listed.
(I will refer to each belief by number after listing them)
Beliefs:
1. DE caused from excess fat
2. DE caused from head trauma*
3. DE from tank reflection
4. DE from strong light
5. DE from looking down
6. DE from genetics
Meaning:
1. DE is caused by an arowana eating too many fatty foods like feeder goldfish. The fat builds up behind the eye and pushes it down, causing DE.
2. DE is caused by an arowana hitting the tank sides too hard. The trauma or shock from it losens the eye from its socket and the aro develops DE.
3. DE is caused by the tank reflecting light. The light reflects into the arowana's eyes and cuases DE.
4. DE is caused by strong lights. The arowana is bothered by the light, thus it has to look in a different direction and the eyes look down and DE develops.
5. DE is caused by an arowana looking down. No matter the cause, whether it be becuase of light or becuase it is looking for food, when it looks down, it starts to get used to it and eventually becomes permanent thus having DE.
6. DE is caused by genetics.
What Doesn't Makes Sense?
1. If DE is caused by fatty foods, then why do only some aros get it? Why can't we prevent DE by feeding lean foods if it is caused by excess fat buildup? Why don't blacks or africans get DE even if you gutload them with feeders?
2. If DE is caused by head trauma, why would asian aros be less prone to get it than silvers? Why would they have DE in the wild if there is really nothing for them to ram their head into in the wild?
3. If DE is caused by light reflections going into the eye, then why can't it be cured by simply turning off all the lights and not letting any light get to the arowana?
4. If DE is caused by the arowana looking in a different direction due to lights, why can't we just cure it by turn off all lights and wrapping the tank in black?
5. If an arowana gets DE by looking down, why can't we just take away all factors that make it look down?
6. If DE is caused by genetics, what makes almost all, if not all, silvers get DE while only a selected number of asian arowanas able to get DE?
What Makes Sense?
1. When you think about it, when humans gain weight, they get bigger and bulkier. If an arowana worked the same way, there could be fat build up behind the eyes thus pushing it out.
2. We always see it in the movies, someone gets hit in the back of the head, and their eyes come popping out, this can also apply with an arowana when the arowana rams into the tank glass. This would also explain why silvers and aussies are more prone to get it than asian arowanas. Silvers and aussies are very jumpy and skittish arowanas, they will dart when they get scared (which is very often) and is not surprising if it hits the tank glass while asian arowanas are more calm and will not be scared as easily, thus explaining while asian arowanas are less prone to DE. African arowanas are also the calmest out of all arowanas, which would mean it would rarely dart into the glass, thus, rarely ever having head trauma.
3. Lights are harmful, especially to the naked eye. If human eyes can be hurt by light, arowanas might also be the same.
4. It is basic reaction that when something is shot at your eye, you either block your eyes from it, or you move your eyes elsewhere. Arowanas have nothing that can shield their eyes, thus they would need to look elsewhere.
5. Humans have habits, so do fish. If we start to slouch for a long period of time, we will be accustommed to it, same can be said for an arowana looking down.
6. Genetics would explain why silvers are very prone to DE while blacks are virtually immune to it even though they are both very similar. This would also prove why you cannot prevent or cure it.
*Special Point* Have you noticed the asterisk on point number 2? The theory that head trauma causes DE is the ONLY theory that has been proven, not just by one but by many people. Bderick67 is one of those people who have personally witnessed his own silver arowana develop DE in just a mere 30 minutes right after it jumped out and hit its head.
Has a good basis for understanding what DE is. Since this is a highly debatable subject I'm sure it will end up with many a posts. For reference here is a pic of a 27" silver aro with severe case of DE,
