If you recently backwashed your DE filter, recharged with new powder, and now notice white clouds drifting in your pool, don’t worry. This is normal, particularly for Las Vegas pool owners during heavy use in the summer months. The good news? It’s usually a simple fix.
There’s a reason why so many Las Vegas pools use DE (diatomaceous earth) filters: While sand filters catch particles as small as 20–40 microns, DE filters stop debris as tiny as 5–10 microns—such as algae spores, pollen, and even dust from our desert storms. That’s how you achieve crystal-clear water.
But with such accuracy comes additional maintenance. When DE powder finds its way back into your pool, it typically indicates that something within your filter isn’t functioning properly, such as a punctured grid or a loose seal. In this guide, we will reveal what causes it and how to repair it quickly before it causes expensive damage.
What Exactly Is DE, and Why Do We Use It?
DE is a white, crystalline powder that is composed of fossilized remains of very small water organisms known as diatoms. When pool filter diatomaceous earth is used, it can filter the equivalent of 2-5 microns. For reference, that’s roughly 100 times finer than what sand filters are capable of filtering.
In Las Vegas, where dust storms and desert debris are common, DE filters are extremely popular. They are the preferred choice for approximately 30% of residential pools in our area, particularly in neighborhoods with extensive landscaping where leaves, pollen, and small particles are constantly found in pools.
When DE Powder In The Pool Becomes a Problem
You know you’ve got DE filter powder in the pool when:
- White, chalky residue appears on your pool floor shortly after backwashing
- Cloudy water that doesn’t clear up despite proper chemical balance
- A film of powder floating on the surface or settling in corners
- Your usually crystal-clear water looks like someone dumped flour in it
The thing is, when you do see a little bit of DE after adding new powder, that’s okay – we’re referring to a light dusting that settles and gets vacuumed up on your next cleaning. When you have large quantities of DE powder in the pool regularly, however, that’s when you know that something is amiss with your system.
The Most Common Reason Behind DE Blowback
1. The “Oops, I Added Too Much” Scenario
Enthusiastic pool owners who believe more DE equals better filtration. Wrong! Every DE filter has its capacity – usually 3 pounds for DE2400 filters, 4.5 pounds for DE3600, and 6 pounds for DE4800 models. When you use more than those quantities, the extra pool diatomaceous earth has no place to go but into your pool.
2. Torn or Damaged Filter Grids
This is the major one – and too bad, the most frequent reason we see on our service calls. Your DE filter grids are really fabric sleeves that contain the DE powder and permit clean water to get through. With time, these grids can tear, particularly in our hot desert climate where temperature swings and mineral-laden water wear them out.
Even a small tear – we’re not talking pinhole-sized – can lead to DE filter powder in the pool. Your pump pressure pushes the powder through those vulnerable areas, producing that annoying white cloud in your water.
3. Manifold Problems
The manifold is the backbone of your filter system – it’s what keeps all the grids together and distributes the water evenly. When manifolds break down (and they will, particularly after 5-7 years of Las Vegas heat cycles), DE powder in the pool becomes a certainty.
4. Backwash Valve Issues
A faulty backwash valve can produce pressure imbalances that drive DE through the system in the wrong direction. This is especially true in older multiport valves that have not been regularly serviced.
5. Missing or Broken Air Relief Components
Your filter’s air relief system helps maintain proper pressure. When these parts fail, pressure bursts can blow DE back out through your returns.
Step‑by‑Step: How to Stop DE Blowing Back
Here’s a fail‑proof checklist to banish DE powder in the pool for good:
1. Backwash & Rinse Properly
- Backwash until the sight‑glass water runs clear (usually 60–90 seconds).
- Switch to Rinse for 15–30 seconds to re‑settle the DE media.
- Return to Filter mode before adding any DE.
2. Measure DE Exactly
- Read your filter’s label: D.E.2400 = 3 lbs; 3600 = 4.5 lbs; 4800 = 6 lbs.
- Wear a mask, slowly pour the DE into the skimmer while the pump runs on “Filter.”
- Wait 5–10 minutes before running any backwash or rinse cycles.
3. Inspect & Replace Grids/Laterals
- Annually, shut off the pump, relieve pressure, and open the filter tank.
- Remove grids and visually inspect each for tears or clogs.
- Replace damaged grids (kits cost $150–$300), or the entire set if they’re over 6–8 years old.
- Check laterals for cracks—replace as needed (around $20–$50 each).
Service the Manifold & Valve
- Remove the spider gasket under the multiport handle; if it’s torn or hardened, replace it ($15–$30).
- Lubricate seals with approved silicone to maintain a tight seal.
- Inspect the manifold for warping or damage; if you see leaks during operation, consider a professional tune‑up.
5. Annual Deep Filter Cleaning
Even with optimal backwashing, DE picks up residual oils and minerals on grids. A yearly “soak and power‑wash” brings peak performance back.
- Soak grids in a barrel with DE filter cleaner for 24 hours.
- Rinse gently with a pressure washer (keep nozzle 12” away).
- Reassemble and add fresh DE.
When to Call Nationwide Pool for Filter Cleaning
If this is a lot, or if you’ve already attempted DIY and continue to notice DE powder in the pool, our trained professionals make it easy:
- Comprehensive Filter Service: We backwash, rinse, strip, and soak your grids, pressure‑clean them, swap out gaskets, and recoat with precisely the right amount of DE.
- Equipment Inspection: We inspect your pump, strainer basket, multiport valve, and plumbing for leaks or wear that might push DE back into the pool.
- Transparent Reporting: You get a detailed report on what we did, the grid condition, and any recommendations.
- Flexible Plans: Weekly, monthly, or quarterly filter‑only packages to keep DE blowing back at bay.
Nationwide Pool has been keeping Vegas pools clean since 1981; let our local experience protect your DE filtration investment.
Enjoy a DE‑Free Swim
Managing pool diatomaceous earth blowback is annoying, but it’s rarely a disaster. The majority of problems are the result of either operator mistakes (excess DE) or routine wear parts (damaged grids). The solution is methodical diagnosis and correct repair. At Nationwide Pool, we’ve resolved thousands of Las Vegas homeowners’ DE filter problems over our 40+ years of operation.
Ready for crystal‑clear water?
Contact Nationwide Pool at (702) 435‑6060 for expert diagnosis and reliable solutions. After four decades of keeping Las Vegas pools sparkling, we know exactly what it takes to get your system running perfectly again.