Why Doesn't My 55 Actually Hold 55?

lyotim88 · Apr 1, 2009

so i recently filled up my 55 gal tank with RO water. My only question is why did it only hold about 47 gallons? the tank has nothing but 2 koralias and a heater, no substrate, nothing. it's completely filled to the top. any ideas?

bronzecat · Apr 1, 2009

Have you measured the actual dimensions that the water is taking up? then use the calculator and see what it comes out as :good:

Inchworm · Apr 1, 2009

Hi lyotim88

I'm just curious, but did you get your tank from Petland Discounts? The old ones I bought from them look bigger than the newer ones, but I thought that might have been an illusion, since the new stands are definitely shorter.

lyotim88 · Apr 1, 2009

thanks for the replies. I actually bought the tank second hand, but it is AGA. I was wondering if maybe 5 gallon buckets actually hold more than 5 gallons? because i used those and filled them up to the top. The tank is a standard 55-48"x12"x21", but if you actually do the math it comes out to like 52 gallons. I just don't know...lol

so does this mean i have to take into account the difference in volume when it comes to adding my LR, i suppose so, right?

bronzecat · Apr 1, 2009

Hi

Yeh, the LR will displace a fair amount of water. More than i thought anyway :crazy:

I would imagine that once your LR is in it'll work out about 48/49 gallons'ish, maybe less depending who much you put in of course. I think there is a formula somewhere that gives a rough idea?

I think with buckets, when they say 5 gallons it doesn't mean right to the top. On mine the level is about 3" short of the top of the bucket, so if you filled it quite high then you have probably put in more than you thought :good:

lyotim88 · Apr 1, 2009

thanks. i figure it has to be the buckets.

oh, and with the LR thing, i meant taking the volume into consideration for lbs/gal

fatheadminnow · Apr 1, 2009

lyotim88 said:
so i recently filled up my 55 gal tank with RO water. My only question is why did it only hold about 47 gallons? the tank has nothing but 2 koralias and a heater, no substrate, nothing. it's completely filled to the top. any ideas?

2 1/2 mini 12 3/16 x 6 1/8 x 8 1/8 2.6 27
5 1/2 Gallon 16 3/16 x 8 3/8 x10 1/2 7 62
10 Leader 20 1/4 x10 1/2 x12 9/16 11 111
10 Long 24 1/4 x 8 1/2 x12 5/8 16 116
10 Gallon 24 1/4 x12 1/2 x12 3/4 21 170

15 High 20 1/4 x10 1/2 x18 3/4 22 170
15 Show 24 1/4 x 8 1/2 x16 5/8 22 170
20 High 24 1/4 x12 1/2 x16 3/4 25 225
20 Long 30 1/4 x12 1/2 x12 3/4 25 225
25 Gallon 24 1/4 x12 1/2 x20 3/4 32 282

29 Gallon 30 1/4 x12 1/2 x18 3/4 40 330
30 Gallon 36 1/4 x12 5/8 x16 3/4 43 343
30 Breeder 36 3/16 x18 1/4 x12 15/16 48 348
33 Long 48 1/4 x13 1/2 x12 7/8 52 382 X
37 Gallon 30 1/4 x12 1/2 x22 3/4 45 415 X

38 Gallon 36 1/4 x12 5/8 x19 3/4 47 427 X
40 Breeder 36 3/16 x18 1/4 x16 15/16 58 458
40 Long 48 1/4 x12 3/4 x16 7/8 55 455 X
45 Gallon 36 1/4 x12 5/8 x23 3/4 66 515 X
45 Long 48 1/4 x12 3/4 x19 60 510 X

50 Gallon 36 7/8 x19 x19 5/8 100 600
55 Gallon 48 1/4 x12 3/4 x21 78 625 X This does equal 55 gallons.

60 Gallon 48 3/4 x12 7/8 x23 7/8 111 710 X
65 Gallon 36 7/8 x19 x24 5/8 126 775
70 Gallon 48 7/8 x19 x21 5/8 165 865
90 Gallon 48 7/8 x19 x24 5/8 182 1080
100 Gallon 72 7/8 x19 x19 5/8 189 1180

120 Gallon 48 7/8 x25 x25 5/8 230 1430
125 Gallon 72 7/8 x19 x23 5/8 236 1480
150 Gallon 72 7/8 x19 x28 3/4 358 1850
180 Gallon 72 7/8 x25 x25 3/4 430 2230

20 X-High 20 1/4 x10 1/2 x23 3/4 32 232
30 X-High 24 1/4 x12 1/2 x24 3/4 41 340
50 X-High 30 1/4 x12 3/4 x30 1/2 98 590
80 X-High 48 7/8 x14 x30 3/4 200 990
110 X-High 48 7/8 x19 x30 3/4 228 1320

10 Hexagon 14 1/2 x12 9/16 x18 3/8 12 110
20 Hexagon 18 3/4 x16 1/4 x20 5/8 23 220 X
35 Hexagon 23 1/4 x20 3/16 x24 3/4 43 390 X
60 Hexagon 27 1/4 x24 1/8 x29 1/2 110 750 X
26 Flatback 36 1/4 x12 1/2 x16 5/8 42 300 X

4 Designer 8 1/4 x8 1/4 x18 7/8 9 49
6 Designer 8 1/4 x8 1/4 x24 7/8 10.5 70
10 Designer 13 5/8 x13 5/8 x19 18.5 115
15 Designer 13 5/8 x13 5/8 x25 25.5 175

It looks like you measured to the nearest inch, make sure you measure to the nearest 1/4 of an inch.

-FHM

bronzecat · Apr 1, 2009

lyotim88 said:
thanks. i figure it has to be the buckets.

oh, and with the LR thing, i meant taking the volume into consideration for lbs/gal

I doubt whether a few gallons will make much difference to the amount of LR needed to be honest. My tank is around 40gals and i have near on 28kgs of LR. As long as you have enough to sustain the biological filtering process of your intended stock :good:

saz326 · Apr 2, 2009

Looks like the tank is measured in imperial gallons rather than in U.S. gallons.

55 gallons u.s. is 47.59 imperial gallons.

Could that be it?

pippoodle · Apr 2, 2009

saz326 said:
Looks like the tank is measured in imperial gallons rather than in U.S. gallons.

55 gallons u.s. is 47.59 imperial gallons.

Could that be it?

good idea tank could have been meant for uk market ???

wolfwolf · Apr 2, 2009

You measured the outside dimesions, but the water is inside the glass and the glass is probably at least 1/4" thick (maybe 3/8"). Could that be the difference?

Math check.... at 3/8" I get 50.9 gallons.

lyotim88 · Apr 2, 2009

saz326 said:
Looks like the tank is measured in imperial gallons rather than in U.S. gallons.

55 gallons u.s. is 47.59 imperial gallons.

Could that be it?

very interesting.. by imperial you mean UK, right? That sounds like a reasonable explanation I just can't see someone shipping a tank overseas, plus it's the same dimensions as a US 55 and its made by all-glass.

saz326 · Apr 2, 2009

lyotim88 said:
very interesting.. by imperial you mean UK, right? That sounds like a reasonable explanation I just can't see someone shipping a tank overseas, plus it's the same dimensions as a US 55 and its made by all-glass.

Imperial - Yeah kinda. We used to have the "imperial" system before "metric" came in. Back when things were measured in feet and inches and we could buy a pound (lb) of meat at the shops. These days we are all standardised in europe. Measure in centimetres, and weigh in grammes.......Although still measure distance in miles in the UK. Very strange.

........And ofcourse America played with the metric system for about 20 minutes and decided Nah - We'll just make our Gallons smaller so nothing makes sence anymore.

(Joking!)

I can only think that the company wanted it to sound bigger than it is. Maybe your bucket is in UK gallons but the tank is in U.S. gallons.

So the tank may actually be 55 U.S. gallons, but your bucket is in UK gallons so you actually measured 47 uk gallons which is 55 u.s. gallons. ....Goodness this is confusing.

Did you buy your bucket in the UK? strange thing to export but it takes all sorts! :lol:

saz326 · Apr 2, 2009

From Wikepaedia - Now it gets mad - America have wet and dry gallons!!!!! Wha???

The U.S. liquid gallon is legally defined as 231 cubic inches,[1] and is equal to exactly 3.785 411 784 litres (1 L = 10−3 m3) or 0.133 680 555… cubic feet. This is the most common definition of a gallon in the United States.

The U.S. dry gallon is one-eighth of a U.S. Winchester bushel of 2150.42 cubic inches, thus it is equal to exactly 268.8025 cubic inches or 4.404 883 770 86 litres. The U.S. dry gallon is less commonly used, and is not listed in the relevant statute, which jumps from the dry quart to the peck.[1]

The Imperial (UK) gallon was legally defined as 4.546 09 litres. This definition is used in Commonwealth countries and Ireland, and is based on the volume of 10 pounds of water at 62 °F. (A U.S. liquid gallon of water weighs about 8.33 pounds at the same temperature.) The Imperial fluid ounce is defined as 1/160 of an Imperial gallon. As from 1st January 2000 it ceased to be legal within the United Kingdom for economic, health, safety or administrative purposes[2].

...Okay. Now you know. :huh: