Home › Fishes › Fish Library

Conversions, Calculations, and Data

Temperature Conversion

  • Fahrenheit = 9/5 Centigrade + 32
  • Centigrade = 5/9 Fahrenheit - 32
Centigrade Fahrenheit
15 59
20 68
25 77
30 86
35 95

Water Hardness

  • German degree (dKH or dGH) = 17.9 ppm
  • Degrees "General Hardness" (GH) = 0.056 ppm CaCO3
  • Degrees "Carbonate Hardness/Alkalinity" (KH) = 0.056 ppm CaCO3

US / Metric Conversions

  • 1 ppm = 1mg/L
  • 1 ounce (oz) = 28.35 gm
  • 1 pound (lb) = 16 oz = 0.4536 kg
  • 1 Liter = 0.264 Gallon
  • 1 Gallon = 3.89 Liter
  • 1 Gallon = 231 cu inches (in3)
Gallons Liters
5½ 21.4
10 38.9
20 77.8
30 116.7
45 175
50 194.5
75 291.7
90 350
120 466.8
  • 1 Meter = 39.4 inches
  • 1 Inch = 2.54 cm
  • 1 Foot = 12 inches = 0.3048 m
  • 1 Yard = 36 inches = 0.9144 m
  • 1 square inch (in2) = 6.4516 cm2
  • 1 square foot (ft2) = 144 in2 = 0.093 m2
  • 1 cubic inch (in3) = 16.387 cm3
  • 1 cubic foot (ft3) = 1728 in2= 0.028 m3

Tank Size, Weight & Pressure Calculations

Note: The weights used in this section are approximate and to be used for estimating only! The calculated weights DO NOT include the additional weight of your stand or interior decorations (i.e. rocks, ornaments, gravel, etc.).
1 gallon of H2O = 8.6 lbs

Example:

30 Gallon tank (36 x 12 x 16) = 6912 in3
6912 in3 / 231 in3/Gallon = 29.92 Gallons of H2O
29.92 Gallons x 8.6 lbs/Gallon = 257.33 lbs of H2O
257.33 lbs of H2O + 43 lbs empty tank weight = 300.33 lbs full weight

Tank Size
/ Shape		 Dimensions
(inches)
(L x W x H)		 Empty Weight
(lbs)
Glass Tank		 Full Weight
(lbs)
5 1/2 Gallon 16 x 8 x 10 7 54.6
10 Gallon 20 x 10 x 12 11 100.3
10 Hexagon 14 x 12 x 18 12 124.6
20 High 24 x 12 x 16 25 196.5
20 Hexagon 18 x 16 x 20 23 237.4
30 Gallon 36 x 12 x 16 43 300.3
45 Gallon 36 x 12 x 23 66 435.9
50 Gallon 36 x 19 x 19 100 583.8
60 Hexagon 27 x 24 x 29 110 809.6
65 Gallon 36 x 19 x 24 126 737
75 Gallon 48 x 18 x 21 140 815.5
90 Gallon 48 x 18 x 25 160 964
120 Gallon 48 x 24 x 25 215 1287.2
150 Gallon 72 x 18 x 28 338 1688.9
180 Gallon 72 x 24 x 25 338 1946.3

The pressure at the bottom of the tank: Pressure per square inch (psi) = Total Weight  / Tank bottom area (L x W)

Example:

30 Gallon tank = 36 in x 12 in = 432 in2psi = 300.3 lbs / 432 in2 = 0.695 psi
0.695 psi x 144 in2/ foot2 = 100 psf

Note: Standard building code uses 75 psf loading on a single wood joist. Therefore, in the above example, you should actually place this tank across 2 floor joists. Don't forget the additional weight of your tank stand, gravel, and interior decorations.

No votes yet