You should backwash your DE pool filter about once a month during pool season. In addition to the regular schedule, you'll want to perform additional backwashing if: You've been running your pool filter for 48 hours straight. This can cause a pressure build-up, even if the filter grids look clean.
Diatomaceous Earth (D.E.) Filter
The D.E. needs to be replenished once the filter is turned back on. Every three months the filter should be taken apart, the grids should be hosed off, and visually inspected for any rips or tears that will cause D.E. to blow back into the pool.
For New Filters or Full Cleaning
Eventually, of course, you'll have to replace the powder with a complete clean of your filters. You should do a total DE filter cleaning one or two times per year, as long as you are backwashing your filter every one to three months.
After backwashing, new DE must be added to the filter. Add the entire amount of DE the filter recommends. If you see DE returning to the pool, vacuum it to waste, after it settles. The next time you backwash and recoat, decrease the amount by 1 pound.
When the pressure rises 8-10 PSI above the starting pressure, it is time to backwash or clean the filter. After the filter is backwashed or thoroughly cleaned, by taking it apart and hosing it out, you will need to pre-coat the filter again with the entire amount of DE stated on the filter label.
If you do not add enough DE to your filter, then the grids are not totally coated with DE and the dirt that goes into your filter will attach itself right to the fabric on the grids and will not backwash off. This will cause your filter to short cycle (go very short times between backwashing).
DE particles are microscopic and have many sharp edges, trapping fine dirt particles that would otherwise be able to get through the sand. Small amounts of DE can be added to a sand filter after each backwash to improve the filtering.
You should backwash your DE pool filter about once a month during pool season. In addition to the regular schedule, you'll want to perform additional backwashing if: You've been running your pool filter for 48 hours straight. This can cause a pressure build-up, even if the filter grids look clean.
Bottom line, the filter must be backwashed on a regular basis to ensure that your pool water is clear. "When do we need to backwash?" - It is recommended to backwash your filter once every 4-6 weeks of regular use.
Adding too much DE to your pool may cause multiple negative results. These ramifications include a clogged skimmer, turning the pool cloudy, reducing the circulatory pressure in the pool and putting too much work on your pump that may result in eventually breaking the pump.
A DE Scoop is specially designed to measure DE powder and 1 scoop is equal to 1/2 lb. of DE powder. To determine how many scoops or coffee cans of DE your filter requires take your filter square footage and divide by 5 (this would be after a full cleaning).
This leaves your pool a cloudy, muddy-looking mess. Luckily however, the powder usually sinks to the bottom of the pool. The only way to remove the earth from your pool is to vacuum the pool with the filter release valve open. This will allow the earth to flush from the filter.
Do not operate your filter pump without having the D.E. powder coating the grids, or you will see the filter pressure rise very quickly, and if left in this manner the grids can collapse or the fabric can become clogged or damaged. As the pressure gauge on a D.E. filter increases, flow rate decreases.
Turn the lever to RINSE, start the pump and rinse for about 15-30 seconds. Stop the pump and turn the lever to FILTER. This is the normal operating position. Close the drain outlet valve and start the pump.
Open the air bleeder assembly on your filter and turn pump on. Watch the pressure gauge for spikes. After the hose fills with water, backwash your sand filter for 2 - 3 minutes, or until water runs clear.
That said, many pool owners backwash weekly as part of their summer maintenance routine, often after they vacuum to collect the remaining particles that are often stirred up.
The most common reasons why a cartridge, sand, or DE filter's pressure rises quickly, even after cleaning or backwashing, is a clogged or blocked filter, algae or old filter elements. If any of these things are wrong, the pressure can rise rapidly in minutes, hours or days.
Grids usually last a long time, up to about 10 years unless they are subjected to extreme conditions for extended periods.
Overall, the lessons learned today is you should run your pool pump an average 8 hours a day to properly circulate and clean your water. The pump should push your entire pool in gallons in this 8 hour period of time. Residential pool water only needs to be turned over once daily to have proper filtration.
Adding DE To Your Sand Filter
That is what makes DE filters top of the line when comparing the three different filter types. However, DE powder can also be used with sand filters to improve their filtering quality. You can add small amounts of DE powder to your filter after each backwash to improve your filterability.
It may take one to two cups of DE powder, but when adding this powder to a sand filter for the first time, only use 1/4 cup at a time. Any time after the first initial successful use of DE powder in the sand filter, you can add the total amount of powder at one time.
How Much Sand to Add to Pool Filters? Sand filters are not filled completely full of sand, but only about 2/3 full, to allow “Freeboard” space in the tank, above the sand bed.