How I can figure out how many gallons of water my pond holds?

It’s important to know the size of your pond so that you can provide the proper equipment as well as be able to apply water treatments with the right dosage. There are several ways to go about it and most folks follow the example of LENGTH times WIDTH times DEPTH then multiplied by 7.48. That rule is a bad one to follow because it tends inflate the ponds volume. Instead, I suggest my rule which is LENGTH times WIDTH times AVERAGE DEPTH multiplied by 7.48. Then take that number and deduct 15% from the original number. I do this to factor in uneven sides so that I get a more realistic number. This will give you a better idea of how many gallons your pond is.

If you have a round pond, I suggest doing the following: TOP DIAMETER times BOTTOM DIAMETER times AVERAGE DEPTH Multiplied by 0.785. Then take 15% off of that number to get a better idea of your ponds volume. Now, if you are just starting out or you’re just refilling your pond and you happen to have a water meter on your house, then you’re in luck because here is an easy approach that is very accurate: (1) Go to your water meter and write down the number that is on the meter. (2) Go fill your pond. (3) When your pond is filled, go back to the meter and write down the number that is on it. (4) Now take the first number and deduct that from the second number and that is how many gallons your pond is!

If you don’t have a water meter on house, here is another simple way to figure out pond volume: (1) take a five gallon bucket and time how long it takes to fill up that five gallon bucket. (2) If a five gallon bucket takes thirty seconds to fill then your flow rate is 600 gph. If it takes 15 seconds to fill, then your flow rate is 900 gph. Now that you know this, simply go and fill up your pond, but be sure to keep track of your start time and end time. Let’s say your flow rate is 600 gph and that it took 3 hours for your pond to fill up, then you would have 1800 gallon pond.

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