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Cylindrical aquarium housing 1,500 exotic fish bursts in Berlin

theguardian.com

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Re: Cylindrical aquarium housing 1,500 exotic fish bursts in Berlin

#251

Post by petre »

weinzierl wrote: post #189
barbegal wrote: post #117

From an engineering perspective these sorts of acrylic tanks are a nightmare to ensure they are safe. The seams are impossible to inspect rigorously so the only real way of checking that they are safe is to load them with an excess pressure ( https://en.wikipedia.org/wiki/Hydrostatic_test ). This can't be done with a tank of this size so the engineers can only real fall back on giving the tank excessive safety margin…

I just saw a documentary (in German) from 2003 about its construction. There is an interview with a guy from the American (Colorado) company which built the tank who boasted that only two companies in the world could build it and the other one declined because they deemed it impossible. Other interesting facts were: - 15 segments of acrylic glass - 12 segments for the outer cylinder, 3 for the inner - all segments wo…

Great engineering feat but it was a dumb idea to begin with. Just like sending people to Mars. Luckily nobody died, excluding the fish of course.

Re: Cylindrical aquarium housing 1,500 exotic fish bursts in Berlin

#252

Post by petre »

fwungy wrote: post #162
pvaldes wrote: post #145

Earlier quoted context omitted.

A tropical aquarium is keep at the same temperature. Unless somebody would disconnect it to save energy or the termostat[s] would fall, shouldn't have experienced a lot of changes in their volume by this.

The hotel was required to reduce its lobby heating due to energy sanctions.

Maybe the insurance companies could sue the government if this was indeed the case. I would really like to see the bad policy makers go to jail or get hit with huge fines.

Re: Cylindrical aquarium housing 1,500 exotic fish bursts in Berlin

#253

Post by chmod775 »

bombcar wrote: post #171
mardifoufs wrote: post #152

Earlier quoted context omitted.

From my limited knowledge[0], it does not seem like this would be an easy structure to scan for inspection. Acrylic can even used for the wedges that interface between the phased array (or single element) probe [1] because it's very good at not interfering with ultrasounds. Water is also a very good "coupling" material, which makes it even harder to get a useful scan since there would be no "backwall" reflecting back…

So it sounds like you'd need something on both sides of the "glass" kind of like this aquarium magnet but much larger/complicated: https://www.amazon.com/JRing-Aquarium-Cleaner-Aquariums-Clea... and slowly move it around the whole tank, repeatedly scanning as it goes. So I'm going to put it in the "theoretically possible but nobody will do it" category for now. ;)

They had divers regularly going inside to clean it anyways. Doesn't seem like such an unlikely thing.

Re: Cylindrical aquarium housing 1,500 exotic fish bursts in Berlin

#254

Post by cardiffspaceman »

Fricken wrote: post #2

Weird. Earlier today I awoke from a nap after strange dreams and attempted to produce images in midjourney of a giant aquarium breaking. I must psychic or something.

In my reading I have read of several such occurrences, and experienced one myself. On 2 Feb 1990 I fell asleep in front of the TV and dreamed I was a journalist in Cape Town, South Africa. There was buzz about a possible speech by F.W. de Klerk in front of Parliament. I was concerned that I needed a snack on the way, and hoped that the gov't would provide donuts. Then I woke up and CNN was nagging me that de Klerk was about to address Parliament. The subject was South Africa transitioning out of apartheid.

Re: Cylindrical aquarium housing 1,500 exotic fish bursts in Berlin

#256

Post by UnquietTinkerer »

swader999 wrote: post #200
jacquesm wrote: post #197

Earlier quoted context omitted.

That's a good guess, but I'd still like to see the final report if and when it is published and whether or not they manage to find the root cause. Likely the differential made the problem worse to the point that something gave but I suspect that there is a deeper underlying cause that made it sensitive to that difference in temperature to begin with. Either a material flaw, an assembly issue or something else.

I'm basing it off of what this guy is reporting. He seems to have an inside legit view. https://www.zerohedge.com/user/105370

Wow, that guy is ... extreme. I'm glad you posted the link, but I'd personally take any conclusions he draws with a grain of salt.

Re: Cylindrical aquarium housing 1,500 exotic fish bursts in Berlin

#257

Post by UnquietTinkerer »

fwungy wrote: post #180
krisoft wrote: post #165

Earlier quoted context omitted.

Do you have a source on that?

Too early for an official RCA, but the surrounding facts of the known temperature sensitivity of the aquarium, the energy reduction mandates in Berlin, and the unusual cold point to that as the most likely cause. This poster on Zerohedge provides more details: I am directly involved in the legal cleanup of this and can provide a little more detail as to what actually happened (Tyler, reach out to me you have my email…

Someone else posted a link to the source for this quote: https://www.zerohedge.com/user/105370.

The writer pretty clearly has an axe to grind with the city, the sanctions, the war, and a lot more (read some of his other comments). His conclusions might turn out to be true, but I don't think he cares if they are or not.

Re: Cylindrical aquarium housing 1,500 exotic fish bursts in Berlin

#258

Post by Slartie »

UnquietTinkerer wrote: post #257
fwungy wrote: post #180

Earlier quoted context omitted.

Too early for an official RCA, but the surrounding facts of the known temperature sensitivity of the aquarium, the energy reduction mandates in Berlin, and the unusual cold point to that as the most likely cause. This poster on Zerohedge provides more details: I am directly involved in the legal cleanup of this and can provide a little more detail as to what actually happened (Tyler, reach out to me you have my email…

Someone else posted a link to the source for this quote: https://www.zerohedge.com/user/105370 . The writer pretty clearly has an axe to grind with the city, the sanctions, the war, and a lot more (read some of his other comments). His conclusions might turn out to be true, but I don't think he cares if they are or not.

Also, the guy uses the "Reichsflagge" as his user picture, which is a pretty sure indicator of him either being one, or at least sympathizing with, right-wing nutjobs. These people are very quickly jumping to conclusions that fit into their irrationally-distorted picture of the world. And very bad at accepting even obvious facts that counter their worldview.

Re: Cylindrical aquarium housing 1,500 exotic fish bursts in Berlin

#259

Post by fuzzfactor »

jacquesm wrote: post #197
swader999 wrote: post #168

Earlier quoted context omitted.

The hotel was told to lower their temperatures. With cold weather outside the differential between the tank and the lobby is the most likely cause.

That's a good guess, but I'd still like to see the final report if and when it is published and whether or not they manage to find the root cause. Likely the differential made the problem worse to the point that something gave but I suspect that there is a deeper underlying cause that made it sensitive to that difference in temperature to begin with. Either a material flaw, an assembly issue or something else.

Seems to me it must have been a salt water tank if it had clownfish, and they are tropical so it's not just exposing the acrylic to constant warm water, but a more realistic marine environment.

In the lab I've chemically tested acrylics that were bullet-resistant at low-cm window thickness. No bullets were used in my phase of the operation, but I was clipping off chips from the exact coupons which had been physically measured beyond the fracture point.

You can tell there's a difference in ductility and brittleness with temperature. Pretty tough stuff regardless.

In the aquarium these are supposed to be very thick-walled acrylic curved panels bonded together.

If the water was maintained warm enough for the reef fish while the ambient air dropped below freezing I don't like that idea. The entire temperature differential being borne by the thickness of the acrylic could mean there are different plastic properties diverging among the inner and outer surfaces of the "glass" panel. This could give rise to stress being concentrated deep within the panel if the transition is not too smooth.

Conditions like this could be recreated if so.

Might have been OK if they had penguins and cold-water fish this time of year.

Re: Cylindrical aquarium housing 1,500 exotic fish bursts in Berlin

#260

Post by swader999 »

elliekelly wrote: post #231
swader999 wrote: post #200

Earlier quoted context omitted.

I'm basing it off of what this guy is reporting. He seems to have an inside legit view. https://www.zerohedge.com/user/105370

Zero Hedge is not a reliable source of information. They also tend to push a lot of Russian fake news/propaganda. And of course Putin would love to have a major news item showing how the West’s gas sanctions have harmed the West.

Yeah, it's a nice balance to the murican propaganda.
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