Volume Of A Hexagonal Tank

[backtotropical]

I realised recently whilst helping a fellow member through PMs that I know how to work out the volume of a hexagonal tank.

If anyone is interested, I can elaborate. It might make a good pinned topic, or addition to the aquarium calculator?

Cheers

BTT

 

[Schmill]

For those happy with the maths it shouldn't be too much trouble, but for those that aren't (and those that like to cheat for speed!), it would be a useful addition to the aquarium calculator, especially if it is a 'common' tank design?

 

[Rooster]

Just a cylinder aint it ? Thats how I would solve it

 

[OldMan47]

A hex is easy to figure. Think of the tank as a rectangle with a triangle on each end. We all know how to calculate the rectangle so all we need to do then is figure the 2 triangles. Since they are both the same size, you can treat them as if they were one rectangle with dimensions of A and B. The original rectangle was figured as the product of B and C.

If the hex is equilateral like the one in the picture, it is even easier. In that case, A is half of C. That means that AREA = 1.5 (C x B) and to get the volume just multiply by the height.

 

[Rooster]

I would have thought :
Measure flat to flat, and treat it as the diameter of a cylinder ?

 

[OldMan47]

That would come up with the volume of an inscribed circular tank. It would be slightly less than the tank we wanted to measure but not a terrible estimate. If you got say 30 gallons that way, just figure it might be more like 32 or 33. .

 

[rdd1952]

In the diagram above, I don't think A = 1/2C (not measuring it but from what I remember from past math classes). It's been a long time since I've been in school and had a math class but as I remember, the area of a hexagon is the length of a side squared times 2.6. For the diagram above, that would be C squared X 2.6. Then you have to multiply by the height. So if the tank had sides of 12" and 18" high, the volume would be 12*12*2.6*18 = 6739.2ci or about 29 gallons.

 

[OldMan47]

That is the same answer as mine RDD. I didn't do all the calcs because it can be a bit daunting but the length of B is C times the square root of 3. The square root of 3 times 1.5 is 2.598 which is close to 2.6.

 

[rdd1952]

Ok, that makes sense as the actual number to multiply by is 2.598 instead of 2.6 but that's a little more complicated than just saying 2.6. I think you can also get there by multipling the square of the narrowest width (face to face length) by .866.

 

[backtotropical]

No need for me to tell you then..........

 

[Miss Wiggle]

or, get a 1litre jug and fill the tank up with it, count how many litres you use

geez you guys are better at maths than me

 

[onebto]

I am with Miss Wiggle on this one but I used a bucket that has litres and gallons marked on the inside

 

[Rooster]

This isnt an exact science though.... you are only calculating the volume for say meds etc... and substrate, rocks etc ALL need to be taken into account !
Counting buckets gets my vote... K.I.S.S. !!!!! lol

 

[waterdrop]

Rooster, I think MW wasn't asking for a K.I.S.S. because she's got her arms crossed.

~~waterdrop~~

 

[Dave L]

It's all very interesting but why complicate it

(C+A) X B X Height = Volume

If you measure in cm just divide your answer by 1000 and you have litres.



MW is spot on though if you need it precise, just don't let anyone interrupt you when you are counting buckets, don't want to have to start again eh?