Retroactively measure QT volume

[starypotter]

Hi everyone,
When I filled in my QT I wasn't paying attention and didn't think things over. As it's just QT I only have some PVC, fake plants, and other decorations and a small HOB filter.
I'm getting ready to start my treatments and I don't know my actual water volume. My plan would be to remove all of the decorations, turn off the filter so the water empties out, and then mark the water line. Then I can drain out a gallon or two and make the new water line, then I will know that the water went down for example 1inch for 2 gallons, I would then be able to measure how many inches of water there are to calculate how many gallons are in the tank.
Do you think the handful of plants and things is making too big of an impact, would I be safe only taking out some of the bigger things and leaving the plants in for my measurements? I don't want to stress my fish out by removing all hiding places and then go around siphoning things they're still rather skittish when I go up to the tank.

 

[Retro Reefer]

Just remove decorations cut off your pump like you said then measure length x width x height of water and divide that number by 231 it will give you the total volume of water in gallons.

 

[User]

Just remove decorations cut off your pump like you said then measure length x width x height of water and divide that number by 231 it will give you the total volume of water in gallons.

This is the way to go.

You can then calculate how many gallons in 1 inch, then you can get very accurate measurements of how much water you remove etc by measuring the change in depth in inches.

For example- for my 180 (72x24x24”)
72x24x24= 42624 cubic inches
42624/231= 184.5 gallons (outside measurement of glass so a little high)

72x24x1= 1776 cubic inches
1776/231= 7.68

1” depth in my 180= approx 7.7 gallons.

This is really useful because it means I know how much drain-down I’ll get to my sump if my return nozzle is 1” below the surface (unless I drill an anti-siphon hole).

 

[starypotter]

Just remove decorations cut off your pump like you said then measure length x width x height of water and divide that number by 231 it will give you the total volume of water in gallons.

This is the way to go.

You can then calculate how many gallons in 1 inch, then you can get very accurate measurements of how much water you remove etc by measuring the change in depth in inches.

For example- for my 180 (72x24x24”)
72x24x24= 42624 cubic inches
42624/231= 184.5 gallons (outside measurement of glass so a little high)

72x24x1= 1776 cubic inches
1776/231= 7.68

1” depth in my 180= approx 7.7 gallons.

This is really useful because it means I know how much drain-down I’ll get to my sump if my return nozzle is 1” below the surface (unless I drill an anti-siphon hole).

Fair enough, I was worried it might not be accurate enough but I'll just do the internal measurements, I'm planning to start copper at one point so I just want to make sure that I know as close as possible so I can raise it slowly with the right amounts. Thanks!

 

[User]

Fair enough, I was worried it might not be accurate enough but I'll just do the internal measurements, I'm planning to start copper at one point so I just want to make sure that I know as close as possible so I can raise it slowly with the right amounts. Thanks!

Best thing you can do fur your copper regimen, is to get a Hanna copper checker. Makes using copper almost full proof. Very easy to check abs keep things in proper range

 

[starypotter]

Best thing you can do fur your copper regimen, is to get a Hanna copper checker. Makes using copper almost full proof. Very easy to check abs keep things in proper range

Alright got one of those so I'm set.

 

[User]

Nice [emoji106]