about the fat drop eye theory

[sodenoshirayuki]

how do you explain De on wild fish then???I say its just a genetic trait.

Its true asian aros are a different species from silvers, but how would you explain that only a couple asian aros get DE if its caused by genetics? And i note that asian aros rarely flip out and bash their head on the glass. Id still think its the head trauma. We all know aros are jumpy fish. They sometimes jump out of water to catch food. I dont see how one unlucky jump couldn't get them hit on the head.

 

[StripeGirl]

i saw a movie at the boston aquarium in the 1980's there were many with DE.I wish i could direct you to a link or video but i can't.Maybe some one else know the film?

 

[StripeGirl]

well maybe the DE in asian arowanas is just much less genetically possible?

 

[Bderick67]

I agree with this. Maybe this summer, or whenever i have time ill try to prove it. Im thinking of fixing my leaking 180 gal and cover each "wall" with huge bags filled with the soft filter media, and then drape a layer of plants over the bags. Ill get a new silver aro. By doing this, the aro wont be able to see out of the tank, thus calming it down, and ill also have really dim lights so it'll be like a constant acclimation process. it will be treated like all the other aros i have, so it'll be eating the same thing, at the same time, with the same feeding schedule, and when it hits 16-20" we might finally be able to prove what cuases DE.

You'll have to do the bottom too.

Actually the only way I think this could be done would be a huge tank, say 10'x10', with no cover. Possibly slopped sides or at least round. Basically simulating natural conditions and eliminating most all potential head banging hazards.

 

[StripeGirl]

besides mine smash the top every day wouldn't there eyes be all Dropped?

 

[sodenoshirayuki]

well maybe the DE in asian arowanas is just much less genetically possible?

So its just a coincidence that asian aros rarely get freaked out and ram their heads, while silvers get freaked out at every small thing and do ram their heads?

 

[StripeGirl]

my blue/black hits the top of the tank every day why no drop eyes?

 

[StripeGirl]

my community of silvers never just freak out and smash into things.They do jump at the top all the time?

 

[Cypher]

The theory of genetics makes more sense to me, as it explains why Asians and Black arowanas seem less prone to DE than silvers.

However Ive had a situation where ive moved my silver (8") from a 75 to a 180 gallon. He became very restless in the bucket during acclimation, bumping into every part of the bucket. By the time i moved him into the 180, the right eye was slightly dropped. Possibly due to head trauma?

So I guess both theories have their own validity.

 

[Bderick67]

my blue/black hits the top of the tank every day why no drop eyes?

Again, blacks aand silvers are different fish. Blacks seem to be immune from DE.

my community of silvers never just freak out and smash into things.They do jump at the top all the time?

Good to hear, I'm sure the large tank helps. I know you have one large silver without DE. Have you seem any of your others develop DE? Considering all your aros you got when they were quite large. Other then your black have you grown out any of your aros from around the 15" range?