Who is good at math???

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reefobsessed

Aquarium Advice Freak
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Since math is not by strong point 8O Can someone give me gallons on a tank I am having made??

It is a pentagon 17 1/2 in front 16 down each side, 271/2 on each side to the back. 36 inches deep...... The site calculators wont figure this one out...

Thanks in advance :D :D
 
I'm confused on the numbers... if it's a petagon, then I'm assuming you have five sides of equal length (looking down on the tank). What are the lengths of those sides. Then tell us what the height is. That's the only info needed.
 
They are not of equal size..You are thinking of a Hex. If you are standing looking at the tank front, the front line is 171/2, then it runs at a slight angle back at 16 down each side where it then jets into the corner & the two back pieces meet that fit together in the back, they are 271/2 on each side then come to a point. It is then 36 inches deep.. Does that help or hinder??
 
I got 67.6 gallons on your pentagon shaped tank but I had to add the sum of all sides and divide equally so it should be close (16+16+17.5+27.5+27.5=104.5)(36")
 
Snapcrackler Im impressed... & thrilled I should be able to shove 150 LBS of LR in that and my Mandarin will be happy & healthly... Thanks for taking the time to figure that for me. :D
 
is the angle in the rear where the two 27.5" sides meet 90 degrees?

What is the distance from middle of the front face to the rear point?

With those two pieces of info i can get you an exact number.

Jim
 
You're welcome. As yaksplat said if you can give him the distance from the inside of the front face to the inside of the rear point and also the angle where the two 27.5 pieces meet then a better calculation could be made.

I just did a generic calculation by dividing up and equaling out the sum of the five side widths so I am bound to be off a gallon or 2.
 
Yes 27.5 is meeting on a 90 in the back. Two 45's meeting in the corner is 90 right?? Anyway the distance from the front to the back is about 31 inches.... Thanks
 
Not sure why Yaksplat (a.k.a. Jim) asked for the measurement from the back (27.5 and 27.5 vertex angle, i.e. where those peices meet) to the front. However, recall that the Yaksplat is a bit of a wizard so he may have a better way, but in his absense I'll give it a shot. It seems that you actually need that measurement from that angle to the vertex on either side of the 17.5 inch front. Since that length is only slightly bigger than your 27.5/27.5 angle to the front length, I estimated the other to be 32 given that information you can split the irregular pentagon into three triangles as Follows:

See attachment

27.5, 16, 32
27.5, 16, 32
31.5, 17.5, 32

Using Heron's formula S=(a+b+c)/2 and then square root of s*(s-a)(s-b)(s-c)

these are the areas of each triangle:
220 Sq In
220 Sq In
270 Sq In

Total area of the pentagon is then 710 Sq In.

Volume of tank is then 710 Sq In (area) * 36 In (height) = 25560 Cubic Ins

Gallons = 25560 Cubic Inches / 231 Cubic Inches per Gallon = 110.6 Gallons.

Yikes:

So it is roughly 110 Gallons.
 
I have a friend who owns a glass shop. I am having it custom made...He is using 1/2 inch glass & a special sealant...
 
Oh my GAWD.... Now thats some inpressive math.... 110 gallon... Boy Id better get on Liverocks.com & get an order in the mail.... THANKS guys....
 
Well I guess that answers your question "who is good at math" LOL!

:wave: "not me!"

pphhtt.

Sorry........
 
Not so far off SnapCrackle you were just a little conservative :)

"Any man who is under 30, and is not a liberal, has not heart; and any man who is over 30, and is not a conservative, has no brains."
- Sir Winston Churchill (1874-1965)

We'll assume you're over 30

:) :)
 
TheMadNucleus said:
Volume of tank is then 710 Sq In (area) * 36 In (height) = 25560 Cubic Ins

Gallons = 25560 Cubic Inches / 231 Cubic Inches per Gallon = 110.6 Gallons.

Yikes:

So it is roughly 110 Gallons.

Okay, I was forced to get an exact solution in autocad. Based on the 31" measurement it will be 109.7 gallons. So in that case in concur.

I just cheated a little and didn't feel like doing all of the trig, but it ended up being a 30 second answer.

well done TMN (y)

you're one T short of a ninja turtle.....

Jim
 
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