Do backgrounds cause strange behavior?

[jus85411]

I don't get the reflections thing. We see reflections because we're outside the tank looking through glass/water. If you were inside of the tank, you wouldn't see any reflections. Fish don't see their reflections when they look at the side of the tank, they see through it, like a window.

agreed 100% i even took my underwater camcorder into my fish tank cause my roommates girlfriend kept saying "he thinks he has a twin" then lets out the most annoying giggle i have ever heard. so i wanted to prove her wrong. but when you have a solid colored background then the fish will see a shadow type reflection. i think it may be the netting thing, or the blue is making them trip out. i dont have a background but i have puffers and ever since i switched them to a bigger tank they are a little more skittish than before. now any movement in front of the tank they swim away from then come out when they realize it might be ok. they are nuts

 

[drb]

Well if I can see my reflection off the background then the fish can to right?

 

[vfc]

It worked! Changing the blue background out calmed all my fish down. My Blood Parrot was always hiding when I had the blue BG; when I switched over to a nature plant back ground, he was out in front of the tank within an hour. See the before and after pics below.

BTW - I put the blue background on the same size tank in the un-finished part of the basement (no traffic). The fish in that tank, who have been relatively calm, are now skittish.

The blue reflective background is definitely the cause of panic.

 

[SpeshulEd]

Well if I can see my reflection off the background then the fish can to right?

To some extent...I guess.

Physics fun:
http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=43
http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=16.0

I believe a lot of it depends on the critical angle.

 

[Drew_H2o]

Maybe the blue makes them think of open water, something that they wouldn't like so they hide around decorations and stuff?

 

[yeroc1982]

My GT used to just sit ans stare at the plant backround but now i put a long mirror there and he always swimming around now, sumtimes attacking himself in the mirror.

 

[Tojo09]

My tank was doing the same exact thing. All my jds and such just flipping. AFTER doing EVERYTHING, i put up some tin foil on the sides of the tank and they all do fine. I believe its because peoples shadow would bounce around every side and make them fill surrounded by something huge.