Garden Pots Melbourne

What is the average temperature of backyard pond in Melbourne?

So I want to make a pond yard and I really want to know what is the average temperature of the pond in Melbourne, Australia.

Here is what the pond will be like: There will be no concrete or anything. Just a liner and rocks covering the bottom. All walls will be at an angle of 70 degrees, so they do not fall apart. The pond will be square and 700x670 (in meters). There will be two levels, that is 1.2 meters deep at the end, it will be 2.6 meters and is 40 centimeters and 60 centimeters at the deep end. There will also be a cave in the deep end, which is 100x100x100 (cm), the roof of the cave is covered by a rock solid, the gap allows the interior will be just big enough for full development man to fit in. This means that the deepest point in the basin is 3.6 meters deep. The shallow level will of course be on the outside, this will also help people who have fallen out (I have a dog but no children under 14).

There will be soft rock at all levels, the rocks are low (no grit), but still low. The rocks will be potted plants on top of the plant is covered with rocks so that the Koi does not uproot. There will be lots of plants and being in the deep end. All these plants can help keep the water much warmer. There will also be a waterfall on the deep pond in the middle of the waterfall is on the corner of the end of depth, it will be rolled out across the deepest part , going to the other two corners of the pond, but it will not go through, as you can tell the waterfall is quite large, about 6 feet long and shaped of <. The water will come down across the waterfall, the waterfall is also a little stream, the farthest from the middle of the water is lowest, it will be the downfall of water will be entirely in raids on both sides to help distribute water across the waterfall so that there will be water coming down from everywhere. It will also stick a bit so you can sit inside the waterfall and see the water coming down.

Outside the pond, there will be beautiful brick, three stacked on each other, it goes around the pond. Between the first and second brick brick, there will be a gap, this gap is to let all the water that flows out over the side and go into the garden. The pond will be in the sun for about 8 hours. This is the weather forecast on average in my area: http://www.bbc.co.uk/weather/world/city_guides/results.shtml?tt=TT003020

So how hot will the water in a pond like this? Try to make it as accurate as possible, Thanks:)

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