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High Filter Pressure

High Filter Pressure

High filter pressure can be caused by the following:
  • Algae clogging the filter
  • Too much PHOSfree added at one time (or added to a dirty filter)
  • Not enough DE added when recharging the DE filter
  • Dirty Filter

If PHOSfree has been used to treat for phosphates, it may raise the filter pressure. If too much PHOSfree has been added, you may notice a high pressure reading. A good rule of thumb is to check the flow from the returns before backwashing or cleaning the filter. If the flow is half way from normal, then the filter can still run. If there is hardly any flow then the filter must be cleaned or backwashed.
Please note that if the filter is cleaned or back washed then the PHOSfree is no longer in the filter. 
It is important to start the phosphate removal process with a clean filter.  
For DE filters, if pressure is really high then turn the filter off for 30 seconds and turn back on. This should help alleviate some of the pressure.
  • When adding PHOSfree, do not add more than 1L at a time. This will help keep the filter pressure down so the phosphate removal process can proceed for a full 48 hours.
Important for DE Filters: If using PHOSfree Commercial Strength, DO NOT add more than 1L at a time. Filter must be back washed and re-charged with DE before adding a second dose. PHOSfree Commercial Strength is also added to the pool water not the skimmer with DE filters.  

Dirty Filter

Over time, such things as dirt, organics (body lotions, hair, dead algae, debris) collect in the filter which will reduce filter cycles. To clean the filter without harsh chemicals, we suggest using Filter Perfect.

Filter Perfect is a highly concentrated deep cleaning solution that removes deep set oils, grease and scum build-up on pool and spa filters. It is very effective on cartridge elements, DE filter grids and sand filters. Filter Perfect improves filter efficiency and lengthens cycles between filter cleaning.

Please see Instructions or Download-PDF in tabs on left hand side for "Product Directions" 

MSDS available for all products on the product page


High Filter Pressure

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