Pool filter sand should not be reused because the roughness of the particles that is used to catch unwanted bacteria, contaminates, and debris will be too worn down to be effective. Reused pool filter sand can result in severe contamination of your pool and is not worth the risk.
There are two ways to clean your sand filter: through backwashing, or deep cleaning. Backwashing involves reversing the flow of water through your filter to flush it out, and is the most common method. It should be done fairly regularly (usually weekly) according to your maintenance schedule.
The sand in your pool filter needs replacing every three to five years, sometimes even longer if your pool remains in relatively good condition when it's open. If you run your pool filter often all year and have a heavy bather load, the sand may need replacing sooner than three years.
Sand filters should be cleaned at least once per season, preferably in the fall before closing. You must clean your sand filter after encountering bouts of algae.
On average, sand should be replaced every 3-5 years. This may be longer if the pool stays clear, or shorter, if the filter runs all the time. The jagged edges of the sand wear down and become smooth as the sand ages.
If you've noticed that the backwashing cycles have become shorter, then you should check to see if the sand filter is dirty or greasy. If the filter is dirty or greasy, then don't be surprised if it takes on the appearance of sandy lard. When this happens, the water doesn't flow through the sand filter media.
Changing the pool filter sand is a bit of a pain, especially in the back region, but a bag of pool filter sand costs around R90 at your local Builders Warehouse, and you should only need two bags for most pool filters.
How Often Should You Backwash a Pool Sand Filter? As a general rule of thumb, you should backwash and rinse your filter about once a fortnight. The optimal time is right after you vacuum the pool. However, if your pool has had a lot more use than normal, it may be necessary to backwash once a week.
After the hose fills with water, backwash your sand filter for 2 - 3 minutes, or until water runs clear. Shut off the pump motor and push the T-handle back down into locked position. Turn your pump back on and note the lower pressure.
Replacement sand for your sand filter typically costs around $25 per 50-pound bag, and your filter may require 100 to 600 pounds or more depending on the size and model. More than likely, you'll need about 350 pounds of sand for an average-sized inground pool filter.
Because play sand, also known as sandbox sand, is less expensive than pool sand, pool owners are often tempted to try using it in the pool filter. Play sand and pool sand are not the same, however, and are not interchangeable.
It is categorized as a Health Hazard Carcinogen Category 1A, because it contains crystalline silica (quartz).
Volume = (width x length x depth) x 0.037
For a rectangular pool that's 18 feet long by 9 feet wide, you'd need at least 1 cubic yard of sand for your base.
You can reuse the filter sand if it's still in good shape. Generally, pool filter sand lasts about 5-7 years before it wears out and needs to be replaced (except for very small filters used on aboveground pools, which usually need new sand much sooner.
Can You Backwash Too Much? If you backwash your pool too much i.e. time duration and/or close frequency then yes you can cause a lot of problems. Some problems that can arise from backwashing your sand pool filter too much are: Loss of water – 500+ litres of water can be lost in each backwashing cycle.
At their very best, sand filters only filter down to around 20 microns. Anything finer than that isn't able to be easily filtered and will generally pass right through the filter and back into the pool. As these particles build up they will cause the water to look cloudy.
The most likely cause of sand at the bottom of your pool is that it simply fell in the water. This can happen even if you don't have sand around your pool. Wind can pick up sand particles and carry it long distances. So the wind may have dropped some sand in your pool on the way through the neighborhood.
The most common problem is a cracked lateral, which is one of the perforated pipes at the bottom of the filter that catches water that has circulated through the sand. Whether it's a lateral, the standpipe, or a seal that is worn or broken, you can usually fix the filter yourself, but it may take a few hours.
Your sand filter is designed to operate effectively with a certain level of sand in it. When the sand level in the filter housing or sand tank is too high, then you may notice sand coming out of the backwash lines when you backwash or use the rinse function.