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.
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).
If your pool is relatively clean then running it for a little while without DE shouldn't hurt anything.
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.
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.
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.
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.
DE Blow-Back: If DE powder is coming into the pool, you may have torn filter grid fabric. Or, you could have a cracked top manifold, or missing air bleeder. The standpipe o-ring could be missing, or the filter valve could be allowing some DE powder to bypass the filter as you add it new.
ADD DE POWDER - Remove the cover to the skimmer closest to the pump and filter. Slowly add the required amount of DE Powder into the skimmer. If you simply dump the DE Powder into the skimmer, you may clog the pipes. CAUTION: WEAR A MASK WHEN ADDING DE POWDER.
D.E. powder is used for D.E. Filters only. It is added into the skimmer. The added powder dissolves in the pipe on its way to the filter tank and coats the nylon-type grids when it reaches them. Water continues to pass through first the powder, then the grids.
Small amounts of DE can be added to a sand filter after each backwash to improve the filtering. The first time you use DE, you need to figure out how much DE to add to your filter. After the first time, you can simply mix the full amount of DE with water in a bucket and pour that slowly into the skimmer.
However, if you can't find a suggestion from the manufacturer, you can use a simple rule of thumb: For a full clean or new filter, add one pound of DE powder for every 10 square feet of the filter. So, a 48-square-foot filter will need about five pounds of DE powder.
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.
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).
Chemically, it is safe to swim. You will need circulation in the pool to introduce chlorine...... keeping it sanitary and algae free. Do not turn your pump off for more than 24 hours or so.
It could be something blocking it, a dirty pool filter, or too much air in the system. If there's something blocking your pump's suction, check your filter gauge. If it's 10psi above the normal reading, clean your filter. This will reduce pressure and reset your pump's flow.
Backwashing a sand or DE filter is a simple task. Shut off the pump, set the multiport valve or slide valve handle to the backwash position, roll out the backwash hose and turn the pump on again. Backwash for 3-4 minutes or until the water runs clear, then shut the pump off and return the valve to the filter position.
If anything could be considered “normal”, it would be about 10 psi. Most filter systems are designed to operate in the 5-15 or 10-20 psi range. The way to find out your particular correct pool filter pressure is to clean or backwash the filter thoroughly and empty the pump and skimmer baskets.
DE has a bulk density of about 20 pounds per cubic foot. 4.8 pounds of DE will have a volume of about 0.24 cubic feet (230 fluid ounces, 7.18 quarts or 1.8 gallons). 4 pounds = about 24 cups. Also, note that most pool stores sell a 1 pound DE scoop (about 48 ounces).
You should clean your DE filter at least once every month or whenever you're pounds per square inch is 8 to 10 pounds above the normal starting pressure. Cleaning your DE Filter involves three basic steps: Backwashing, Cleaning the manifold and grid and adding new DE.
DE Powder. Diatomaceous Earth, used in D.E. pool filters, can also be used in sand filters and cartridge filters to trap particles down to 3 microns in size. Use 1-3 cups depending on your filter size, by pouring it into the skimmer after backwashing, and it forms a layer on top of and down into your sand bed.
You need chemicals with a sand filter because they require sanitization, phosphate removal, pH adjustments, and alkalinity alterations.
If you have a sand filter, a good thing is that you can improve your water clarity by using a DE media + filter aid in the skimmer. Note: You cannot mix any DE filter media with sand or use them in the sand filter tank to replace filter sand—you can only use it in the skimmer.