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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

#171

Post by bombcar »

mardifoufs wrote: post #152
bombcar wrote: post #137

Earlier quoted context omitted.

Is there no way to detect cracks or is it just prohibitively expensive to do so? I know that metal fatigue is a known thing that airlines check for and when they went to carbon fiber they had to develop tools to detect fatigue/cracks.

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. ;)

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

#172

Post by ArchitectAnon »

rjzzleep wrote: post #12
jl6 wrote: post #3

Wow, how do you make pieces of glass that size?

It looks to me as if they're actually a lot of smaller pieces put together, but maybe I see it incorrectly. Maybe one day, architects will stop designing things that are structural liabilities, or engineers actually get to say no to it before construction starts.

Incredibly unlikely for any part of the structure to have been designed by an architect, most likely a highly specialist subcontractor design item. Our insurance would not cover it and it is illegal for architects to practice without insurance in many EU countries. The closest any architect would get to this is to go to a big fish tank company and say I want a big fish tank with diameter x and height y, can you do it and how much will it be...

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

#173

Post by barbegal »

plastiquebeech wrote: post #163
barbegal wrote: post #156

Earlier quoted context omitted.

Not of this size. Certainly single pieces are used in other applications where safety is even more critical such as submersibles. But manufacturing a tube this big would be impossible.

Impossible to manufacture? Or financially impossible to build a factory for the purpose and larger infrastructure to accommodate transportation? I'm curious if there is something about acrylics which makes it impossible to make very large single pieces.

I guess you could transport it at immense cost. But you'd also need a machine capable of moulding or extruding it this big. Current maximum for plastic pipes is about 3.5m diameter https://www.agru.at/en/applications/agruline/grand-opening-r... so you'd need something which is capable of more than 3 times the diameter.

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

#174

Post by seattle_spring »

abduhl wrote: post #144
kayodelycaon wrote: post #135

Earlier quoted context omitted.

The material used is plexiglass, aka acrylic, a type of clear plastic. Actual glass is probably too brittle or expensive. People use "glass" to mean the clear part of a window, not the actual material, in this context.

I'm glad to hear that you'd agree with me then that a correction saying "there is no glass" would be inappropriate because when someone says glass they mean the clear part of the tank.

This may or may not be your intention, but fyi you are coming off as extremely condescending bordering on /r/iamverysmart level tones.

I'm no expert, but I know that a hot tub on slightly uneven ground has a good possibility of bursting and ruining the tub due to how much stress the water will unevenly put against a side. I don't see why the same underlying reasons wouldn't apply here too.

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

#175

Post by jacquesm »

ArchitectAnon wrote: post #166
durnygbur wrote: post #107

Earlier quoted context omitted.

yes they better lawyer up in Germany, correct

Not sure about Germany but in the UK the designers would be unlikely to still be liable anymore under the original contract to design this, liability under the contract would be up to 12 years from when the work under the contract was completed. They might be liable in tort for professional negligence but it's much harder to prove that this has occurred especially after 20 years. More likely the company that was unde…

Or the one that modified it, assuming that's not the one that originally built it.

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

#176

Post by toast0 »

WhackyIdeas wrote: post #74
TeMPOraL wrote: post #41

Earlier quoted context omitted.

Interesting to think about. On the one hand, it's no different than any of the random stuff that happens to fish in the wild, or wildlife in general. Being killed for no reason at all is the default in nature; humans build societies and civilizations and develop technologies in large part to avoid it. On the other hand, this feels especially sad for some reason.

We have an industrial unit which has a mice problem. Every time I go to B&Q (home hardware store for non-UK folk) with the intention of buying mice traps, I just can’t push the button. These mice are destroying our stock, but I just cannot do it. I would be a terrible fisherman.

Have you considered outsourcing? To a cat (or cats) or a pest control company. The pest control company will probably check and close off opportunities for mice to enter the unit, which cats won't do, so you might want to consider retaining both options.

Warehouse cats can be nice warehouse companions too (depending on what happens in the unit).

I've had to do some mouse removal work in my forest adjacent home, and it's not pleasant, but neither is having mice around.

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

#177

Post by jacquesm »

lsaferite wrote: post #111
jacquesm wrote: post #76

Earlier quoted context omitted.

A couple of hours only.

I'm sorry for your friend's loss and for the lost livestock, but it seem like it was simply a ticking time-bomb. If your friend had 30 tanks and thousands of fish, they should have had a more involved backup plan that involved a dedicated generator in addition to a UPS. A small generator would have been a tiny fraction of the materials and livestock costs of running a setup like that.

It was the work of a lifetime. Power here has been so reliable that people forget that it can fail, and even though he was somewhat prepared it turned out not to be enough.

Agreed though that it was a ticking time bomb. As for better backup plans: even autostart generators for data centers can fail when you need them most. Backup plans end up with more and more layers until you think you've got it all and then some little oversight will get you. In his case he probably could have done more but that's only because we're looking at it after the failure, for decades it worked.

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

#178

Post by gnabgib »

usefulcat wrote: post #158
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…

The article specifically says that this particular aquarium was made of glass?

The article does, but "the AquaDom was a 25-metre-tall (82 ft) cylindrical acrylic glass aquarium"[0] Turns out that's just poor reporting, they could have been more specific. It was the largest (by volume) acrylic cylindrical aquarium in the world.

[0]: https://en.wikipedia.org/wiki/AquaDom

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

#179

Post by pvaldes »

krisoft wrote: post #167
pvaldes wrote: post #141

Just to add context we could be talking easily about more than $100,000 lost only in the fishes. The materials and pumps of the aquarium should be much worse. After the strange coup try in Germany the last week, I wouldn't discard still that is not another destabilization attempt by some hypothetical agent. Weren't cameras set around the Hotel hall?

> After the strange coup try in Germany the last week, I wouldn't discard still that is not another destabilization attempt by some hypothetical agent. How would that work? Is this site important enough to destabilize the country?

Only two people injured after a million liter water wave was a miracle. Could have been much worse.

But I'm probably just hypothesizing too much [again] while trying to analyze the case. It just feels strange coupled with the last long chain of strange events happening right now. To be fair, twenty years are a lot of time for an acrylic tank.

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

#180

Post by fwungy »

krisoft wrote: post #165
fwungy wrote: post #157

The issue was caused by the forced reduction in heating due to energy sanctions. The decreased warmth of the lobby caused the aquarium, which was sensitive due to its size and construction, to contract and contort to the point of structural failure.

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 if you'd like to verify my identity here).

The city of Berlin required the hotel reduce the ambient temperature of the hotel lobby to save on energy due to sanctions. Its been abnormally cold in Berlin the past few nights dipping down to -11°C last night and -12°C the night before that. The water is heated to a constant temperature above 30°C for many of the fish species that lived in the tank.

As the nights got colder and colder, the lower ambient temperature of the air surrounding the tank likely started causing deformations and hairline cracks in the bottom of the tank where the pressure is the greatest. Last night at -11° caused the ambient temperature to drop too low given the reduced heating in the lobby and is what it looks like caused the "sudden unintentional disassembly"/catastrophic failure of the tank.

Everyone is already lawyering up including the city, the HVAC manufacturer, tank manufacturer, HVAC installer, building engineer, hotel - the litigation is going to be fun to watch and work on.

What isn't covered in the news is damage. The tank in 2003 cost €13 million. Today its orders of magnitude more expensive to replace, some of the fish were quite exotic and are expensive losses in and of themselves. Then you have the damage to the hotel lobby and façade, electrical components of the building in the three-story basement are also effected and large amounts of water went into the parking garage where many vehicles are parked not only from the hotel and offices but from an attached apartment complex to the hotel.

Losses are tens of millions. All because the city made the hotel turn down the heat.

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