How to Tread Water

Treading water is a basic survival swimming skill, as well as a useful method of staying afloat in the water. It's something you can learn even before you learn to swim. Treading water is also used frequently in aquatic sports like in water polo. Even if you're not the greatest swimmer, you can build your stamina and learn how to tread water for extended periods of time and increase strength throughout your body.

Method1

EditBasic Techniques

1. 
   1
   Use both your arms and legs. Make use of all four of your limbs with your body upright (vertical). If you turn your body horizontal and start kicking with your legs and paddling with your feet, you'll start swimming, not treading water.
2. 
   2
   Keep your head up and your breathing normal. Keep your head above water and try to slowly regulate your breathing. Slowing down your breath will help you calm down, conserve energy, and tread water longer.
3. 
   3
   Move your arms horizontally. If you move them up and down, you'll move up, and then move down again because you have to pull them back up. Move your arms forward and back with your hands closed facing the way they are moving. This will keep your upper body up
4. 
   4
   Move your legs circularly or kick your legs back and forth. If you are moving your legs in a circular fashion, don't point your feet and keep them stiff. If you are kicking back and forth, point your feet downward and kick them constantly.
5. 
   5
   If you need to, lay down on your back and gently paddle your arms and your feet. Give your body a temporary break from paddling by laying down on your back. You'll still have to paddle with both arms and legs, but not nearly as much as you would have to with your body vertical.
6. 
   6
   Hold onto any flotation device if you're having trouble staying above water. A log. A paddle. A rubber boat. Whatever it is, use any type of floating material that you can to hold onto and help keep you above water. The less time you spend using energy to stay above water, the longer you'll last.

Method2

EditTreading Techniques

1. 
   1
   Do the dog paddle. The dog paddle is where you move your arms out in front of you while kicking your legs up and down.

   • The advantage: it doesn't take a lot of "proper technique" in order to do.
   • The disadvantage: it saps you of energy, meaning you won't be able to do this technique for very long.
2. 
   2
   Try the flutter kick. The flutter kick is where you tread water with your legs while keeping your arms outstretched for balance. To flutter kick, point your toes downward and kick one leg forward as you kick another leg back. Maintain a consistent back and forth.

   • The advantage: you can keep your arms free by doing the flutter kick, giving you an opportunity to do something else with them.
   • The disadvantage: because you're using just your legs to keep you up, this technique can be taxing.
3. 
   3
   Do the frog kick. The frog kick is where you bring your feet out to the side, and then back in. The frog kick is also called the whip kick. Starting off with your legs together, move your feet out to the side and then quickly back in.

   • The advantage: this kick is less tiring than the flutter kick or the dog paddle.
   • The disadvantage: using this kick causes you to bob up and down in the water instead of staying relatively motionless.
4. 
   4
   Try sculling. Sculling allows you to tread water with your hands. To scull, keep your hands outstretched to the side and completely submerged. With your palms facing toward one another, move your hands towards one another until they are almost touching. When you've reached this point, turn your palms facing outward and move your hands back out to their original position. Try to keep your hands doing one fluid movement back and forth.

   • The advantage: you can keep your legs free by sculling, allowing you to combine this with another foot treading technique such as the flutter kick.
   • The disadvantage: you have to keep pretty much your whole body (minus your head) underwater.
5. 
   5
   Try the rotary kick. Also called the eggbeater, this is where you move one foot clockwise while moving the other foot counterclockwise. This technique is hard to master, but it saves a lot of energy.

   • The advantage: you save a lot of energy doing this technique if you can perfect it.
   • The disadvantage: this is a hard technique to perfect, and many people need to practice extensively in order to learn it.
6. 
   6
   Try the little helicopter. Lay back in the water in the same manner as floating. Immediately move your hands in a circular motion. Move your feet up and down together.

   • The advantage: it's very simple to explain to children.
   • The disadvantage: circling hands can become tired.

Resource: wikihow.com

How to Calculate Swimming Pool Volume in Gallons

Knowing how much water your pool will hold is the key to having the correct water chemistry, sizing pumps, filters, and more. If you want to be able to calculate your swimming pool volume in gallons, all you have to do is follow a simple formula that is derived from your pool's shape. If you want to know how to do it, just follow these steps.

Method1

EditMeasuring Your Swimming Pool

1. 
   1
   Measure the length and width of the pool. If it's rectangle, just measure the longest side and the shortest side of the pool. If it's a square, just measure one of the sides of the pool -- all four sides of the square will have the same length. And if your pool is round, just measure the diameter of the pool, which is the longest path that can travel through the center of the circle, from one edge to the other.
2. 
   2
   Measure the depth of your pool. This is the other dimension that is crucial to knowing the volume of your pool. If your pool has the same depth throughout -- most above ground pools are structured this way, for example -- then you'll just have to take one measurement from the top to the bottom of the pool. But if, like most pools, your pool has depth that gradually increases, then you'll have to measure the minimum depth (the shallow end) and the maximum depth (the deep end) of the pool.

Method2

EditCalculating the Volume of a Rectangular Pool

1. 
   1
   Find the average depth of the pool. To do this, you need to write down the measurements of the deep end and the shallow end of the pool and divide the result by two. Let's say the shallow end of the pool measures 3 feet and the deep end measures 8 feet. (3 + 8)/2 = 5.5. The average depth of the pool is 5.5 feet.
2. 
   2
   Multiply the result by the length and width of the pool. Now, just take this number and multiply it by the length and width of the pool. You're really just multiplying the area of the bottom of the pool by its depth. Let's say that the width of the pool is 20 feet and the length is 40 feet. So, 5.5 x 40 x 20 = 4,400 cubic feet.
3. 
   3
   Convert the answer to gallons. To convert the answer to gallons, simply multiply the answer by 7.48. 4,400 x 7.48 = 32, 912 gallons of water. You're all done.

Method3

EditCalculating the Volume of a Round Pool

1. 
   1
   Calculate the volume of the pool as if it were a cylinder. If you have a round pool that is of uniform depth, then all you have to do to find the volume is to treat it like a cylinder. To find the volume of a cylinder, all you have to do is find the area of the circular base times the height; this uses the formula V = πr²h. Let's say the pool's radius is 4.5 feet and its depth (height) is 4 feet. Plug those numbers into the formula to find the volume: V = π x 4.5² x 4 = 254.46 cubic feet. To convert this to gallons, simply multiply the result by 7.48. 254.46 x 7.48 = 1903 gallons.
2. 
   2
   Use the shorthand formula for finding the volume of a round pool. For faster but slightly less accurate results, you can also plug the depth and diameter of the pool into the following formula: V = depth x diameter squared x 5.9. Let's say we're working with the same circle that has a depth of 4 and a diameter of 9 (the same as having a radius of 4.5). The volume of this pool = 4 x 9 x 9 x 5.9 = 1,911 gallons. The result is slightly larger.
3. 
   3
   Adjust the formula if your pool does not have the same depth. If your pool is shallower on one end and deeper on the other. just measure the minimum height and maximum height of the pool and divide them by 2 to get the average height, or the depth you should use in either formula. For example, if the pool has a minimum depth of 5 feet and a maximum depth of 10 feet, then you can add 5 + 10 to get 15, and divide 15 by 2 to get 7.5, the average depth of the pool. You can use this as the depth of the pool in either formula.

Method4

EditCalculating the Volume of a Free Form Pool

1. 
   1
   Find the average depth of the pool. Simply find the minimum depth and the maximum depth of the pool and divide the result by 2. Let's say the shallow end of the pool measures 3 feet and the deep end measures 8 feet. (3 + 8)/2 = 5.5. The average depth of the pool is 5.5 feet.
2. 
   2
   Find the average width of the pool. Now, just find the average of all the widths of the pool by adding up the different widths and dividing by the amount of widths. Let's say you're working with a pool that has three widths: 20, 15, and 20. So, add them up and divide by 3. 20 + 15 + 20 = 55. 55/3 = 18.3 feet. The average width of the pool is 18.3 feet.
3. 
   3
   Find the length of the pool. Let's say the length of the pool is 40 feet.
4. 
   4
   Multiply the average depth, the average width, and the length of the pool. So, 5.5 feet x 18.3 feet x 40 feet = 4,026 cubic feet.
5. 
   5
   Multiply the result by 7.48 to get the answer in gallons. 4,026 cubic feet x 7.48 = 30,114 gallons.

Resource: wikihow.com