odd tank size question

[deepseadan]

Years ago I bought a acrylic tank, and the store sold it as a 125 gallon. The dimensions are 60"L x 18"W x 24"T. Then a while back I bought another tank, a 90 gallon acrylic. Its dimensions are the same other than the length which 48" instead of 60". Then in researching gallons and size on the web, I found a web site which you put the dimensions of your tank and it gives you the gallons. My 90 checks out exactly, but my supposed 125 comes in at 112 instead of 125. Anyone know what may be going on?

 

[Deep Seven]

Are we talking US gallons? UK gallons are bigger.

My guess is the manufacturer sold it to the store as a 125g and the store unknowingly re-sold it improperly labelled. Mistake? Scam?

 

[HUKIT]

Most tanks when using a calcuator don't come out to what they are sold as. For instance my 150rr are 72x18x29 which equates to 162.7g, 40B are 36x18x16 which is 44.88g.

 

[deepseadan]

It's US gallons. I actually bought the tank used from the store, someone broke down their system and sold it to them. What makes questions things even more is when I Google the dimensions 60x18x24 it shows different brands selling those dimensions as both 125 and 110. For example, sea clear sells those dimensions as a 125 gallon, and oceanic sells theirs as a 110 gallon. I can't seem to understand what I might be missing. If my tank is a 110 gallon instead of 125, I've been dosing wrong all these years.

 

[HalfMoon B]

Take into count than when the twnk is full of driftwood/live rock/whatever water displacement lowers the amount of water that is actually in the tank. Hukit's calculations are accurate, and I suspect that at this point, mfgs are so engrainede in their labeling (as are consumers) that it would be futile to change the system now.

Think the packaging for hot digs, and hot dog buns...

 

[deepseadan]

Take into count than when the twnk is full of driftwood/live rock/whatever water displacement lowers the amount of water that is actually in the tank. Hukit's calculations are accurate, and I suspect that at this point, mfgs are so engrainede in their labeling (as are consumers) that it would be futile to change the system now.

Yeah, I've been dosing for less for the live rock, sand ect. Also I noticed that usually the tank measurements are taken on the outside. If you minus maybe 3/4" for the thickness (X2) of the acrylic walls, you lose even more volume.

This is the website I was using for calculating volume-

http://animal-world.com/encyclo/information/calculate.htm