Jump to content

Calculating the size of a hexagon tank...


tigerbarb
 Share

Recommended Posts

I found this on www.aquariumfish.net Hope it helps.

The formula for volume is always the base times the height, which you measured 24.75". So all we need is the area of the base.

Since all 6 panels in your aquarium are 12", the base is a so-called regular hexagon with all the sides measuring 12". The area of this regular hexagon is 6 times the area of an equilateral triangle with each side 12".

Now think of a 12" equilateral triangle, and divide into two right triangles with one side 6" and hypotenuse 12". The other side will have a length equal to the square root of 12x12 - 6x6, which equals the square root of 144 - 36, which is the square root of 108, or about 10.4".

The area of the right triangle is 1/2 x 6 x 10.4, and the area of the equilateral triangle will be twice as much, which is 6 x 10.4 = 62.4 square inches, so the area of the base of your aquarium is 6 x 62.4, or 374.4 square inches.

The volume of your aquarium is the area of the base times the height = 374.4 x 24.75 = 9296.4 cubic inches. Now multiply by 0.00433 to convert cubic inches to gallons:

9296.4 x 0.00433 = 40.1 gallons, which answers your question.

When you calculate something like this, and the answer is important, because you may use the answer to determine how much Quick Cure or Salt to add to your aquarium, then it's best to double check your calculation. Or you might end up forgetting that the equilateral triangle has two right triangles, and get an answer that is off by a factor of 2.

Here is one way to double check the answer. The hexagonal base of your aquarium could fit inside a circle with a radius of 12" and have an area of about

pi x 12 x 12 = 3.14 x 12 x 12 = 452.2 square inches

which is somewhat bigger than the 374.4 square inches for the area of the hexagon inside the circle. So that checks.

A circle with a radium 10.4" would fit inside the hexagon, and that circle would enclose an area of about

pi x 10.4 x 10.4 = 3.14 x 10.4 x 10.4 = 327.8 square inches

which is less than the 374.4 square inches for the area of the hexagon. So that checks too.

Also the area of the hexagon should be about half-way between the area of the inner circle and the area of the outer circle. The areas are about 327.8, 374.4, and 452.2, so those numbers look about right.

Now lets check these calculations with a measurement. Your aquarium is 24.75" tall. When you change 20% of water, as recommended repeatedly in this web site, you should remove 20% x 24.75 = 4.95, or about 5" of water. So measure down from the water surface 5" and put a mark on the glass with a marker pen.

Now remove water down to the mark and keep track of how much water you remove. For example, you could use a clean one-pint measuring cup. You should get close to 64 pints, which is the same as 8 gallons, or 20% of the 40 gallons, that we calculated in your aquarium. (Be sure to thoroughly clean the measuring cup, when you finish using it.)

You will probably measure less than 64 pints. Maybe you'll get 61. Because the measurements for your aquarium that you gave in your email were probably the outside measurements, and the water fills the inside of your aquarium.

You could improve the calculations above by doing them again with the inside measurements, and perhaps subtracting the volume of the ornaments, etc. Click here for more about doing that.

I hope this has thoroughly answered your question.

Ok, just found this, lot's less work. http://tools.fishindex.com/

Edited by Rainmaker69
Link to comment
Share on other sites

I found this on www.aquariumfish.net Hope it helps.

The formula for volume is always the ......blah blah blah.......

I hope this has thoroughly answered your question.

Ouch....ouch...ouch...make it stop hurting.

Ouch. :wacko:

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
 Share

×
×
  • Create New...