How to Maintain a Diatomaceous Earth (D.E.) Pool Filter?
A pool filter is one of the most important pieces of any pool equipment pad. Without proper filtration, your pool water will always be full of debris and contaminants, and trust me you don’t want that. Picking the right filter can be difficult if you’re new to the pool world. If you clicked on this article, I assume you’re either considering getting a pool with a diatomaceous earth filter or perhaps you’re interested in upgrading your current pool filter to a D.E. filter. Either way, you’re curious about what it’s like owning and operating a D.E. filter. Like cartridge and sand filters, D.E. filters require a little bit of maintenance throughout the swim season to ensure proper filtration, and we’re here to tell you how to get it done.
Welcome to the final entry in our series on pool filter maintenance. At Royal Pools G2 Landscaping, we have been installing and maintaining sand, cartridge, and diatomaceous earth filters for inground pools for 25 years. We know just how important it is to properly maintain your pool filter, especially when it comes to D.E. filters.
What Is a D.E. Filter? How Do They Work?
A diatomaceous earth filter is one of the three popular pool filter types alongside sand and cartridge filters. The filter is comprised of a hard outer shell encasing multiple grids inside. The filter uses diatomaceous earth media, which is a powdery material made out of crushed seashells or the skeletal remains of microscopic sea organisms. The earth media coats the grids inside the filter which then catches debris as it enters the filter from the pump.
D.E. media can catch debris as small as 5 microns (micrometer: 1/1,000,000 meters), making it the most powerful pool filter on the market when considering which filter can filter the smallest debris.
Maintenance
If you’re looking for a pool filter with as little maintenance required as possible, then a diatomaceous earth filter is not for you. D.E. filters biggest downside for most pool owners is that they are the most maintenance-heavy filter type. In addition to backwashing and replacing part of the media every few years (in D.E.’s case: the grids), you also have to recharge D.E. filters with more earth media after every backwash, and deep clean and fully replace the D.E. once a month.
The primary maintenance practices with D.E. filters are:
- Backwashing, rinsing, and recharging once a week.
- Deep clean filter grids and replace the earth media once a month.
Backwashing
If you read our article about sand filter maintenance, you know how important backwashing is. It applies to diatomaceous earth filters as well! The filter media can only trap so much debris before it loses its filtering power and requires cleaning. Like sand filters, the best way to determine when a D.E. filter needs backwashing is by monitoring the filter PSI weekly. When the PSI rises 8-10 marks above the ideal level the D.E. needs to be backwashed, rinsed, and recharged.
Backwashing is the process of cleaning the filter media of debris by reversing the flow of water so that it comes out of the laterals at the bottom of the filter, travels up through the sand, and catches all the unwanted particles and debris. When the dirty water reaches the top, it is pushed out of the filter through a backwash line.
The backwash process is done by shutting off the pool pump and changing the filter mode from filtration to backwash using a multi-port valve. D.E. filters typically feature a clear glass eyeball near the top of the filter that shows the state of the water while backwashing and rinsing. When you start backwashing, you’ll notice the water in the eyeball turns cloudy or discolored. As the backwash continues, the water should clear up. Backwash until the water looks crystal clear, shut off the pump, and switch the filter valve from backwash to rinse. The eyeball may cloud up momentarily again before returning to crystal clarity. Rinse for 30-60 seconds, turn the pump off, turn the filter back to filtration mode, and then turn the pump back on.
After backwashing your D.E. filter, the final step is “recharging” the D.E. in the filter. When backwashing, much of the earth media in the filter is diluted and expunged from the shell as it is fully dissolved in the water, thus requiring a fresh dose of D.E. to continue filtering properly.
D.E. Lifespan?
As previously stated, a diatomaceous earth filter should be thoroughly cleaned, with the grids sprayed down and the filter filled with brand new D.E., once a month to ensure proper and consistent filtration. For an in-depth breakdown on how to deep-clean a D.E. filter, click here. The earth media itself can sustain in balanced water for a long time, but as you backwash and recharge it multiple times, a buildup of D.E. will grow between the filter grids, or the earth media will become too diluted to filter debris if not recharged properly after every backwash.
The grids inside the filter will also need to be replaced after some time. If the grids get holes, or the plastic inside the grids breaks or decomposes, it is time to invest in a new set of grids. While it varies per filter and dispensing on the conditions of the pool, D.E. grids typically last at least 5 years before showing wear and tear.
Conclusion
We can’t tell you which filter to get, it’s all gonna come down to your personal preference and budget. The truth is that all three filters are great at filtering water in a pool and will keep your pool clean so long as you stay on top of the maintenance. D.E. filters require the most maintenance of the three types of filters, and that is important to note before committing to a filter for your pool. We hope this article helped you determine whether or not a D.E. filter is the right fit for you. For more information on pool filters, check out the articles below. For more educational content on all things pools and landscaping, head on up to our learning center. Below are a few articles/videos to expand your pool knowledge:
How To Maintain A Pool Cartridge Filter?
Pool Buying Guide: 5 Steps to Purchasing an Inground Pool
How To Clean Your Swimming Pool Cartridge Filter
Written By Logan Edgemon