Mirror In Every Tank? Myth?

I'll go dig up my GoPro camera and and see what it does in one of the tanks. It may take a little while,

Max, why did you have your GoPro buried? What's down there to take pics of?

 

Max, why did you have your GoPro buried? What's down there to take pics of?

Good 1. Elvis mabee?

 

Max, why did you have your GoPro buried? What's down there to take pics of?

The GoPro gets used for everything from the dogs, shooting, boating, and the car. From time to time especially lately since I moved things get a little displaced.

 

When we look in the front of our tank at the side walls, we see a mirror. Is that what the fish see? I have seen pictures taken from inside the tank, with no mirroring affect. Can someone test this with a water proof camera? Do Bettas flare at there reflection? do corrys school with there own reflection? These are all reasons given to people who ask. I think fish can see out as well as we can see in. Mabee there is a mirror depending on room lighting? Can we test this?
In the attached photo there is only 1 fish. I can see her reflection, but can she?View attachment 490875

Do you have a set of goggles?

It would be awesome if we were somehow able to design a tank where the fish can’t see their reflections. The fish would be a lot less stressed and they might venture away from the glass more often.

I am sure that it depends on what is external to the tank and the amount of light, and it's relationship to the interior light. Of course a 3D covering (such as a rockscape) on 3 sides would do it, but then you only have front to back viewing. Perhaps you would only need to remove the interior right angles with something not reflective. It inevitably did lead us to the question of reflections in a Bow.
But what about the even more perplexing
...a Hex tank

 

Do you have a set of goggles?

I do. But I'm not climbing in Lol I'll get 1 of the kids to do it.

I am sure that it depends on what is external to the tank and the amount of light, and it's relationship to the interior light. Of course a 3D covering (such as a rockscape) on 3 sides would do it, but then you only have front to back viewing. Perhaps you would only need to remove the interior right angles with something not reflective. It inevitably did lead us to the question of reflections in a Bow.View attachment 492257 But what about the even more perplexing
...a Hex tank

This thread raised lots of questions.
Are some fish comforted by there reflection?

Are some frightened by it?

Should we try to correct it?

How does backgrounds effect it?

Different shaped tanks?

Are we all nuts?
Lol

 

I am sure that it depends on what is external to the tank and the amount of light, and it's relationship to the interior light. Of course a 3D covering (such as a rockscape) on 3 sides would do it, but then you only have front to back viewing. Perhaps you would only need to remove the interior right angles with something not reflective. It inevitably did lead us to the question of reflections in a Bow.View attachment 492257 But what about the even more perplexing
...a Hex tank

I just got a 33g hex tank so when it is set up and running I will see if I can borrow a GoPro and do some tests!

 

I just got a 33g hex tank so when it is set up and running I will see if I can borrow a GoPro and do some tests!

Awesome. Please post those pictures.

 

This thread raised lots of questions.
Are some fish comforted by there reflection?

Are some frightened by it?

Should we try to correct it?

How does backgrounds effect it?

Different shaped tanks?

Are we all nuts?
Lol

Yes we are ALL nuts!! As to the other questions...remains to be seen.

 

Thought I'd revive this thread, and sumerize it a bit. When we look at our tank we see a mirror on the sides, but what do the fish see?

When we look in the front of our tank at the side walls, we see a mirror. Is that what the fish see? I have seen pictures taken from inside the tank, with no mirroring affect. Can someone test this with a water proof camera? Do Bettas flare at there reflection? do corrys school with there own reflection? These are all reasons given to people who ask. I think fish can see out as well as we can see in. Mabee there is a mirror depending on room lighting? Can we test this?
In the attached photo there is only 1 fish. I can see her reflection, but can she?View attachment 490875

Here's some pictures from inside the tank sorry about the quality some it's hard to shoot completely free hand. But the shot angled from the front glass to the side glass shows a mirror on the front glass. Shooting directly through the side glass no mirror. Now one of the other shots is down the length of the tank towards the heavily planted end, you can see the 100 gallon through the front glass without a mirror effect.View attachment 490905View attachment 490906View attachment 490907View attachment 490909

So, while I was doing a fishless cycle I was curious about this very thing so I took a video:

Thee Lady G on Instagram: “A Fish Eye View! I decided to see just exactly what the view really is from the inside of my fish tank. I wanted to know what my fish will…”

So, as you can see, the only reflection I have inside the tank is from the background where I hung a piece of black cloth against the glass. The rest of the tank is like a huge bay window into my room.

I took the cloth down to clean some water stains off of it, and just left it off. I actually like it better, because it feels like the fish are in the room with me, which they seem to like. I think that Sunny would follow me around the house like a puppy if she could.

These pictures are from the inside of the tank. The first 1 is with the room quite dark only a little light from the kitchen on. The 2nd picture is pointed at the corner of the tank with the room as dark as I could get the whole downstairs. As you can see there is a slight mirroring affect. It appears the mirror is directly related to ambient room lighting. If we want the mirror gone we will need to have the room brightly lit. Depending on the lights in the room it may cause excessive algae.View attachment 491196View attachment 491198

The above photos, with the exception of the first, were all taken from inside of the tank. As you can see depending on room lighting there is a mirror. More room light =less mirror. Less room light = more mirror.

 

I do know for sure my bettas see themselves at least sometimes, as they have flared and crashed into their reflections. I do think they have got used to it, don't see such behavior very often anymore

 

I saw you mention this topic in one of my threads and it reminded me that I took a picture like this 5 years ago at an aquarium. It always freaked me out a bit xD

 

IMG_3218

• H2O Concierge
• Mar 23, 2018

10 yr old Botia Loaches

I saw you mention this topic in one of my threads and it reminded me that I took a picture like this 5 years ago at an aquarium. It always freaked me out a bit xD

I saw you mention this topic in one of my threads and it reminded me that I took a picture like this 5 years ago at an aquarium. It always freaked me out a bit xD

Here are a couple of my own. Are there 3 or 4 loaches? Check out the weird reflection of the table next to the tank on a piece of black slate. The pic was taken looking down from the short side of the 75g.

IMG_3218

• H2O Concierge
• Mar 23, 2018

10 yr old Botia Loaches

 

Do keep in mind though, what you see through the front of the tank is *not* what the fish see from the inside of the tank. The only way to really know is to dunk a camera in your tank!

 

Do keep in mind though, what you see through the front of the tank is *not* what the fish see from the inside of the tank. The only way to really know is to dunk a camera in your tank!

I'm actually surprised we don't have more photos on here from INSIDE the tank in the water. If I had a GoPro I would do this and post immediately.

 

I'm actually surprised we don't have more photos on here from INSIDE the tank in the water. If I had a GoPro I would do this and post immediately.

right?? I took video while I was fishless cycling my tank by putting my phone in a ziploc bag, because I was curious what the fish see. I was so surprised about the lack of 'mirror.' I want a waterproof camera to put in my tank and leave there. I wish I could shrink down and just get IN my tank, how fun would that be??

 

The first 2 pages of this thread have a couple of pictures from inside the tank. Not sure why people keep posting pics from the outside.

My tank is actualy large enough for me to climb in and look out, but I fear it would really spook my fish too much.

 

I doubt most ppl have seen this stand up comic...but his name is John Capparulo and he has a bit about fishtanks where he decided against one as a pet cuz he acted out a goldfish seeing its reflection, being shocked, swimming round, and being shocked by its reflection again. Lol. Sorry...just keeps entering my mind as funny every time I see this thread...lol

 

some science on reflection, and light angle

"https://en.wikipedia.org/wiki/Tot... . If light is going from a dense medium like water to a less dense one like air, the angle of incidence increases according to Snell's law. If the angle of incidence is more than 48.471 degrees (arcsin⁡(1/n)" role="presentation" style="display: inline; line-height: normal; word-spacing: normal; overflow-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">arcsin(1/n)arcsin⁡(1/n) where n=1.3358" role="presentation" style="display: inline; line-height: normal; word-spacing: normal; overflow-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">n=1.3358n=1.3358 is the refractive index) on the water side, it would need to be more than 90 degrees on the air side to satisfy the law. In that case it can't get out at all.

Moreover there's a smooth lead-up to total internal reflection. There's always some light that's internally reflected, and the fraction just gradually increases to 100% at the critical angle. So the walls still look fairly mirror-like for angles of somewhat less than 48.4 degrees."

and

"Critical angle – The least angle of incidence at which total internal reflection takes place. The angle of incidence in a denser medium, at an interface between the denser and less dense medium, at which the light is refracted along the interface. When the critical angle is exceeded, the light is totally reflected back into the denser medium. The critical angle varies with the indices of refraction of the two media with the relationship: Sin Ic = n n' Where Ic is the critical angle; n’ the refractive index of the less dense medium, and n the refractive index of the denser medium."
https://www2.optics.rochester.edu/workgroups/berger/EDay/Optics demonstrations for the classroom.pdf

 

some science on reflection, and light angle

" PhD in Physics, The University of Queensland, physicist with National Astronomical Observatory of Japan
· Author has 8.6k answers and 9.5m answer views


It's a case of "total internal reflection": https://en.wikipedia.org/wiki/Tot... . If light is going from a dense medium like water to a less dense one like air, the angle of incidence increases according to Snell's law. If the angle of incidence is more than 48.471 degrees n=1.3358n=1.3358 is the refractive index) on the water side, it would need to be more than 90 degrees on the air side to satisfy the law. In that case it can't get out at all.

Moreover there's a smooth lead-up to total internal reflection. There's always some light that's internally reflected, and the fraction just gradually increases to 100% at the critical angle. So the walls still look fairly mirror-like for angles of somewhat less than 48.4 degrees."

and

"Critical angle – The least angle of incidence at which total internal reflection takes place. The angle of incidence in a denser medium, at an interface between the denser and less dense medium, at which the light is refracted along the interface. When the critical angle is exceeded, the light is totally reflected back into the denser medium. The critical angle varies with the indices of refraction of the two media with the relationship: Sin Ic = n n' Where Ic is the critical angle; n’ the refractive index of the less dense medium, and n the refractive index of the denser medium."
https://www2.optics.rochester.edu/workgroups/berger/EDay/Optics demonstrations for the classroom.pdf

Thank you very much for the detailed analysis and the links. It's much appreciated.

 

some science on reflection, and light angle

PhD in Physics, The University of Queensland, physicist with National Astronomical Observatory of Japan
· Author has 8.6k answers and 9.5m answer views


It's a case of "total internal reflection": https://en.wikipedia.org/wiki/Tot... . If light is going from a dense medium like water to a less dense one like air, the angle of incidence increases according to Snell's law. If the angle of incidence is more than 48.471 degrees (arcsin⁡(1/n)" role="presentation" style="display: inline; line-height: normal; word-spacing: normal; overflow-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">arcsin(1/n)arcsin⁡(1/n) where n=1.3358" role="presentation" style="display: inline; line-height: normal; word-spacing: normal; overflow-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">n=1.3358n=1.3358 is the refractive index) on the water side, it would need to be more than 90 degrees on the air side to satisfy the law. In that case it can't get out at all.

Moreover there's a smooth lead-up to total internal reflection. There's always some light that's internally reflected, and the fraction just gradually increases to 100% at the critical angle. So the walls still look fairly mirror-like for angles of somewhat less than 48.4 degrees."

and

"Critical angle – The least angle of incidence at which total internal reflection takes place. The angle of incidence in a denser medium, at an interface between the denser and less dense medium, at which the light is refracted along the interface. When the critical angle is exceeded, the light is totally reflected back into the denser medium. The critical angle varies with the indices of refraction of the two media with the relationship: Sin Ic = n n' Where Ic is the critical angle; n’ the refractive index of the less dense medium, and n the refractive index of the denser medium."
https://www2.optics.rochester.edu/workgroups/berger/EDay/Optics demonstrations for the classroom.pdf

“Blinded me with science!” Nm...you millennial types won't get it...lol

 

lol i'm actually a Gen Xer

 

Now we really feel old.

 

Okay I got as far as Quantum tunneling . . . Now I know why you Millennials write TL DR.

 

I've noticed this too. Whenever my frogs interact with their reflection, it's always on the side walls, never the front or back.



Then again, my quarantine tank is so old that the front glass seems to be obscured by something that I can't even razor off. Two fish desperately trying to see out.

 

I've noticed this too. Whenever my frogs interact with their reflection, it's always on the side walls, never the front or back.
View attachment 500672

Then again, my quarantine tank is so old that the front glass seems to be obscured by something that I can't even razor off. Two fish desperately trying to see out.
View attachment 500674

It seems like he's interacting with his reflection but he is actually seeing through the glass, it only looks like a reflection from the outside of the tank. Unless you have painted that side black like the back of a mirror, he's seeing out of the side just the same as you see in the front!

 

It seems like he's interacting with his reflection but he is actually seeing through the glass, it only looks like a reflection from the outside of the tank. Unless you have painted that side black like the back of a mirror, he's seeing out of the side just the same as you see in the front!

"Total internal reflection (TIR) occurs when light originating in the medium of the greater index (in this case, water) hits the interface at an angle greater than the critical angle, which is about 48.8º."
"Critical angle– The least angle of incidence at which total internal reflection takes place. The angle of incidence in a denser medium, at an interface between the denser and less dense
medium, at which the light is refracted along the interface. When the critical angle is exceeded, the light is totally reflected back into the denser medium. "

https://www2.optics.rochester.edu/workgroups/berger/EDay/Optics demonstrations for the classroom.pdf

"If you're the sort of person who enjoys swimming, and can either open your eyes underwater or regularly wear a mask or goggles, you've probably notice that the underside of the surface of a swimming pool or other body of water, looks shiny. If you're in a place with cool marine life, you can even get awesome pictures like this:"

"(from this photography guide site which includes some other awesome examples). So, why do you get this effect?

The key physics here is the idea of refraction, which has to do with the propagation of light through matter. You can talk about this in a particle-like picture, if you want, but it's usually described in terms of waves: light waves entering a material slow down slightly due to their interaction with the material, and as a result, their wavelength gets slightly shorter (you can think of it, loosely, as a given wave "catching up" to the wave in front of it as they hit the boundary). A light wave passing from vacuum into glass sees a reduction in speed to about 2/3rds of the speed of light in vacuum, and the wavelength gets shorter by a corresponding amount-- orangey-red light at 600nm would have a wavelength of around 400nm, like that of violet light in vacuum. This is quantified by a number called the "index of refraction," which is a number greater than 1 for ordinary materials; around 1.5 in the case of glass, about 1.3 in the case of water."

Reflecting, Totally; or Why the Pool Looks Shiny from Underwater | ScienceBlogs

more cool pics Reflections

 

Index = 1.7 on my new polycarbonate eyeglasses. Much thinner than glass or acrylics, because they bend the light farther. It doesn't sound like much but glass lenses were twice as thick on me.

 

Index = 1.7 on my new polycarbonate eyeglasses. Much thinner than glass or acrylics, because they bend the light farther. It doesn't sound like much but glass lenses were twice as thick on me.

Polycarbonate is the best way glass is thick and too heavy acrylics are a joke sorry I used to be in the biz

 

Everything depends on lighting and viewing angle, such that you can have anything from no reflection at all to the complete funhouse mirror effect.





These guys can see each other...

 

Polycarbonate is the best way glass is thick and too heavy acrylics are a joke sorry I used to be in the biz

The cost is awful high though, which I believe is why you don't see popular polycarbonate fish tanks.

 

The cost is awful high though, which I believe is why you don't see popular polycarbonate fish tanks.

I agree

 

Everything depends on lighting and viewing angle, such that you can have anything from no reflection at all to the complete funhouse mirror effect.
View attachment 504299View attachment 504300View attachment 504301

These guys can see each other...
View attachment 504302

Great pictures, and very to the point and easy to understand answer, as to the question is there a mirror, and why.

 

Thank you Dave. I didn't actually stick my camera in the tank though. I was just looking through the small end of a long tank.

 

Thank you Dave. I didn't actually stick my camera in the tank though. I was just looking through the small end of a long tank.

Still your answer was correct and easy enough to understand.

I like the scientific explanations about light refraction, but it can get confusing for some.

 

My severum often times tries to fight his reflection in the side of the tank.

 

My severum often times tries to fight his reflection in the side of the tank.

Which brings up another point. For some fish this mirror can be quite stressful, for others( peaceful schooling fish) it's comforting .

 

Everything depends on lighting and viewing angle, such that you can have anything from no reflection at all to the complete funhouse mirror effect.
View attachment 504299View attachment 504300View attachment 504301

These guys can see each other...
View attachment 504302

again, these photos are being taken from the outside of the tank. The fish in the 'funhouse mirror" is not going to see *any* of those reflections except possibly the one on the bottom. You cannot see what they are seeing unless you are *inside* the tank looking out. Yes, it is a matter of refraction, not reflection.

 

I took that particular view because (from the camera's view, not the fish's) both cases are exhibited. If I moved my camera 2" forward thru the glass, the photo wouldn't change, as I'm positioned normal to the end glass.

 

do you notice that both water and glass are both transparent (see through) and yet can reflective (reflect s)?

"At a boundary between two transparent media, light is partially reflected and partially refracted. The ratio of the reflected intensity to the incident intensity is called the reflectance R and the ratio of the transmitted intensity to the incident intensity is called the transmittance T."
Reflection and Refraction

 

The amount of reflection the fish is seeing is based on the angle he/she is looking at the glass and the amount of light on the other side of that glass.

There not seeing as much reflection as we are. In some situations there not seeing any.