# Physics of a tank of water (aquarium on a moving vehicle)

pengyou1
I'm sorry if I am intruding on this forum, but I have a question that requires a knowledge of physics. I am preparing a plan now to convert a school bus into an RV. I have raised tropical fish all of my life and would like to keep doing so. I want to put a 125 aquarium in my RV so that it is perpendicular to the sides. My question: if I keep the tank completely full of water (and fish, gravel, etc) and it is completely covered with no airpockets in the aquarium, will the aquarium behave like a solid mass? I don't want to put baffles in the tank because it would detract from the aesthetic value of the tank, and I am afraid of any sloshing that might occur.

## Answers and Replies

anorlunda
Staff Emeritus

Yes it will behave like a solid mad in those conditions. Moor important, it might behave like a 1400 pound lethal projectile in case of a collision. Your plan sounds unsafe to me.

pengyou1
berkeman
Mentor
More important, it might behave like a 1400 pound lethal projectile in case of a collision. Your plan sounds unsafe to me.
Maybe wire some explosive shaped charges to the aquarium and tie them to collision sensors? That way if there is a collision that could launch the aquarium through the bus, it gets blown up so it's just flying water. (Sorry about the fish...)

https://s7d2.scene7.com/is/image/PetSmart/5257038?$sclp-prd-main_large$

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pengyou1
anorlunda
Staff Emeritus
Start with tempered glass that doesn't break into sharp shards. Then add a crash test. You could probably hire a junk yard to lift and drop a scrap school bus containing a fish tank.

Perhaps easier, ask experienced RV owners about carrying heavy objects at highway speeds.

pengyou1
berkeman
Mentor
Then add a crash test. You could probably hire a junk yard to lift and drop a scrap school bus containing a fish tank.
I think the MythBusters have a consulting buisiness on the side...

anorlunda
gleem
Science Advisor
Education Advisor
Consider if emergency breaking at 60 mph in 180 ft you will experience about 0.8g's of acceleration resulting in a tipping force on you tank of about 1000 lbs . So secure it to counteract this force. Keep in mind that there will be a pressure on the forward glass face . This will result in some leakage. What is the area of the front of the tank.. Can the glass face sustain this magnitude of force? Need to know the dimensions of the tank. For safety purposes add a 50% strength factor for the restraining straps.

berkeman
Mentor
BTW, @pengyou1 -- Are your fish small? If so, can you architect your aquarium system to be several smaller tanks that are easier to secure, all connected by clear hoses? I haven't seen an aquarium system like that, but it might be smart for a vehicle-based system to minimize the size of each tank...

anorlunda
Staff Emeritus
BTW, @pengyou1 -- Are your fish small? If so, can you architect your aquarium system to be several smaller tanks that are easier to secure, all connected by clear hoses? I haven't seen an aquarium system like that, but it might be smart for a vehicle-based system to minimize the size of each tank...

Brilliant!

berkeman