Just some quick math, 16’ x 2.5’ x 2.5’ (30 inches equals 2.5 feet) equals just under 750 gallons. Water weighs 10 pounds per gallon so that would equal 7,500 pounds. Round it up to 8,000 pounds for ease. Divide by 2,000 since 2,000 pounds equals 1 ton and you get 4 tons.
You were about a ton off but a close guess so good job.
I must ask this though, if you’re going to do a tank 16 feet long then why would it only be 2.5 feet wide? In my mind it would look odd.
Also welcome to monsterfishkeepers, we have free coffee and doughnuts by the door

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