Weald Aquatics | Aquarium & Pond Fish Shop in Kent | The Weald Aquatics Blog - General hints and tips


Coolings Green & Pleasant
Main Road, Knockholt, Kent TN14 7LJ

01959 532 963

Opening times

Monday to Saturday
and Public Holidays: 09:00 - 14:00
Sunday: 10:00 - 14:00

As a pet shop, we are exempt from the government's ban on shop closures. So we cautiously welcome you if you need any supplies during this time. However, whilst in the shop please observe the rules on social distancing in order to keep yourselves, other people and our team safe and well.
From Tuesday 24th March Coolings Green & Pleasant are only going to be open from 9:00 am to 12:00 pm each day. (10:00 am to 1:00 pm Sunday). We will still be open after noon until 2pm. If you want to come to Weald after noon then please phone the shop when you get to Coolings so we can open the main door to let you in.
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How to work out the water volume in your aquarium or pond.

Blog post written by Gary | 04 September 2014 | Category: General hints and tips

One of the many questions we ask customers when working out how much water treatment to use or if the correct size UV light system is fitted is the total water volume of their pond or aquarium. Many people don't know how to work this out so we thought a handy guide might be in order.

Working out the water volume is very easy using the following formulas.


In an aquarium to find the capacity in gallons you multiply the length by the depth and the width in inches then divide by 276, so...

L x D x W divided by 276 = total gallons

To change to litres multiply the gallons by 4.546.

For metric measurements multiply the length by the depth and the width in centimetres then divide by 1000, so...

L x D x W divided by 1000 = total litres

For both equations please allow for water displaced by rocks and other ornaments.


As ponds are of course normally larger than aquariums it is easier to use feet instead of inches so a different formula is used.

Multiply the length by the width and the average depth by 6.25 this will give you the total pond volume in gallons, so...

L x W x average D x 6.25 = total gallons

To change to litres multiply the gallons by 4.546.

As ponds are not always a rectangle or square it is best to work out an average length and width as well as an average depth. All pond treatments allow for slight inaccuracies when working out the water volume of the pond.

If you've got any questions just drop us a line!