Calculate Pond Volume Before Buying Viresco Blanket Weed Treatment Or UV Clarifier

I have recently sent out quite a bit of information about various algae types in ponds and treatment using a UV Clarifier or Viresco.

To Recap I would quickly like point out the difference between these pond algae control methods.

  • A UVC Clarifier is the best cure for suspended algae (planktonic algae) that causes green pond water. Viresco will work but opt for a UV Clarifier (UV sterilizer) for crystal clear pond water on an ongoing basis. Forget pond algaecides they are temporary and potentially dangerous to aquatic life if over dosed.
  • Viresco is one of the best ways to get rid of blanket weed in fish ponds. It is shipped world wide from the UK, is fairly low cost, has a long shelf life and ACTUALLY WORKS VERY WELL. There are many pond keepers who believe that barley straw is best for blanket weed removal in ponds ... They haven't tried Viresco yet!

As a few readers of my free newsletter series have reminded me it is important to know your fish pond volume to make the correct decision in terms of what size UV Clarifier to buy or how to measure the right amount of Viresco (or for that matter any pond additive) since the information is often given as X grams per litre or ounces/gallon.

I accept that this can be very confusing if you don't know the volume of the pond.

Lets take the case of Viresco ... 5 grams will treat a pond volume of 13,500 litres or 3000 UK gallons or 3750 US gallons.

If your pond is less then this then of course you don't have to add all the Viresco and thus you can save some of the Viresco for later use.

What Is The Volume of my pond?

Well here's a simple way to get a good estimate which is certainly accurate enough for the specification discussed here.

To make it even simpler you can download a calculator I've created that uses a Microsoft Excel spreadsheet.

Here the principle behind the calculation and it doesn't matter what shape your pond is:

The volume of your pond is equal to the surface area multiplied by the average depth.

So if your surface area is 10 sq feet and the average depth is 2 feet then the volume is 200 cubic feet.

In metric units if your surface area is 3 sq metres and the average depth is 1 meter then the volume is 3 cubic metres which is 3000 litres.

All that you now have to do is work out these 2 variables to calculate your fish pond volume.

The depth is easy... just take a stick, mark the water level and measure the depth this way at various points then take the average.

how to find volume if you know the depth

The surface area is a bit more tricky ... and you might want to refer to the diagram opposite.

Nevertheless this is how you work out the surface area:

1. Imagine the pond is contained within a rectangle ... take a piece of paper and mark out the rectangle shape to a (more less) scale.

2. Sketch within the rectangle the basic pond shape trying to be as close to the relative size as you can get.

3. Divide the rectangle into equally sized squares by drawing parallel lines in both direction on your sketch.

4. Count the number of squares covering the actual pond shape. This will include part squares so estimate the squares made up by adding all the parts as well as the complete squares.

5. Now divide the number of squares coving the pond by the number of squares in the rectangle and you have the proportion of the rectangle covered by the actual pond.

6. Let's use an example:

  • The number of squares in the rectangle = 20
  • The number of squares covering the pond = 15 and a half
  • Then area of pond relative to rectangle = 15.5/20 = 0.775
  • Rectangle area = width x length say 4 x 8 = 32
  • Then surface area of pond = 0.775 x 32 = 24.8 (this could sq feet or sq metres)
  • To get volume multiply 24.8 by the average depth you worked out earlier.

You don't have to be accurate to a couple of inches in your measurement just make a good estimate e.g. by using a measured stride.

To make it even simpler you can download a calculator I've created that uses a Microsoft Excel spreadsheet.

Remember it is a spreadsheet so you will need to have Excel on your computer.

You'll see a complete range of useful pond calculators on this page. Feel free to download all of them if you like.

One of these calculators will let you convert from litres to gallons, cu feet to gallons (and vice versa) and other units too.

blanket weed treatment using Viresco...

As mentioned in previous newsletters Viresco is the best blanket weed treatment and honestly in my opinion the best cure for blanket weed in ponds.

How many pond keepers have asked themselves this simple question "How do I get rid of blanket weed from my pond?"

The answer has always been the same ... Wish I Knew! ... Now, thanks to John McLauchlan we all know. John McLauchlan, is the owner and developer of Viresco Aqua and Viresco Koi the superior blanket weed control and treatment solution.