Three Filter Types — One Job
All three pool filter types accomplish the same fundamental goal: removing suspended particles from pool water as it circulates through the system. They differ in the filtration media used, how fine a particle they capture, how they're cleaned, and how much maintenance they require. All three work in conjunction with a pump — they perform their job passively as long as water is flowing through them.
Understanding Filter Performance Ratings
Pool filters are rated by two independent standards organizations, each measuring performance in a different way. Understanding what these ratings mean helps you interpret product specifications and compare filters across types and brands accurately.
Cartridge Filter
Best Choice for Sun Belt PoolsCartridge filters use a cylindrical element made of pleated polyester fabric housed inside a sealed tank. Water from the pump enters the tank and flows through the pleated fabric, which traps debris — the filtered water then exits through the center and continues to the return jets. The pleating dramatically increases the effective surface area compared to a flat medium, allowing cartridge filters to handle higher flow rates without sacrificing filtration quality.
For most residential pools in Las Vegas and the broader Sun Belt, the cartridge filter is the recommended option. The primary reason is water efficiency: cartridge filters don't require backwashing. Cleaning is done by removing the cartridge, rinsing it with a hose, optionally soaking it in a chemical cleaner for deep cleaning, and reinstalling it. No water is discharged to the sewer — a meaningful advantage in a desert climate where water conservation matters both environmentally and financially.
- No backwashing — conserves water in desert climates
- Good filtration efficiency at 10–15 microns
- Lower operating pressure than sand filters
- No multiport valve — simpler plumbing
- Easy to inspect during cleaning
- Works well with variable speed pumps at lower flow rates
- Cartridges need cleaning 2–4 times per year in Las Vegas
- Cartridges require replacement every 24–36 months in LV conditions
- Cannot be backwashed — must physically remove and clean
- Higher initial cost than sand filters
Single Cartridge vs Four Cartridge
For a detailed step-by-step guide to cleaning your cartridge, including spray vs soak methods and the inspection checklist for when to replace vs reinstall, see our cartridge filter cleaning guide →
Diatomaceous Earth (DE) Filter
Superior Filtration — Higher MaintenanceDE filters use internal grids or fingers covered in a fine powder made from the fossilized remains of tiny aquatic organisms called diatoms. This powder — diatomaceous earth — creates an exceptionally fine filtration medium capable of capturing particles as small as 3–5 microns, including algae cells, bacteria, and fine mineral particles that cartridge and sand filters pass through. For pools where water clarity is the absolute priority, DE filters deliver the finest filtration available in residential pool equipment.
After backwashing a DE filter, fresh DE powder must be added to recharge the filter grids. The powder is typically mixed with water and poured into the skimmer while the pump runs, distributing it through the system onto the internal grids. This recharge step is required every time the filter is backwashed — it's the primary maintenance distinction between DE and the other filter types.
- Finest filtration — captures particles at 3–5 microns
- Removes algae cells, bacteria, and fine mineral particles
- Produces exceptionally clear water
- Effective in warm, UV-intense Sun Belt conditions
- Backwashing can be done in place without removing filter elements
- Requires backwashing — uses 50–100 gallons per cycle
- Must recharge with fresh DE powder after every backwash
- DE powder handling requires care — respirator recommended
- Grid inspection and cleaning required annually
- Higher ongoing maintenance commitment than cartridge
- In Las Vegas, backwash water must go to sewer — not street or landscape
DE filters are an excellent choice for pools with high bather loads, pools that have recurring water clarity issues despite adequate chemistry, and pool owners who prioritize absolute water quality and don't mind the additional maintenance steps. For most Las Vegas homeowners balancing maintenance ease and water conservation, cartridge is the more practical choice — but DE remains the performance benchmark.
Sand Filter
Not Recommended for Sun Belt PoolsSand filters are the oldest and most traditional pool filter design. Water from the pump enters the top of the tank and is forced down through a bed of silica sand — the sand mechanically traps dirt and debris, and filtered water exits through a collector at the bottom of the tank and returns to the pool. When the sand becomes loaded with debris and pressure rises, the multiport valve is switched to backwash mode, which reverses the flow through the sand and flushes accumulated debris out to the drain.
Sand filters are the simplest design and have the lowest initial purchase price. Sand replacement is infrequent — typically every 5–7 years. However, sand filters are the least recommended option for residential pools in Las Vegas and the Sun Belt for a specific reason: they capture particles at 20–40 microns, which means fine desert dust, algae cells, and smaller debris particles pass straight through and return to the pool. In a climate with intense UV and warm water temperatures that accelerate algae growth, that limitation is significant.
- Lowest upfront cost of the three filter types
- Sand replacement only needed every 5–7 years
- Backwashing can be done in place — no element removal
- Very simple multiport valve operation
- Lowest filtration efficiency — 20–40 microns allows fine particles through
- Fine desert dust passes through and returns to the pool
- Requires regular backwashing — uses 50–100 gallons per cycle
- More prone to channeling as sand compacts — further reduces efficiency
- Not recommended for warm-water, high-UV climates like Las Vegas
- Backwash water must go to sewer — same requirement as DE
If your pool currently has a sand filter and you're experiencing persistent water clarity issues or higher-than-expected algae activity, the filtration micron rating is worth considering as a contributing factor. Upgrading to a cartridge filter is a straightforward swap in most equipment configurations. See our filter service page → for a consultation.
Backwashing — What It Is and Why It Matters in Las Vegas
Sand and DE filters are cleaned through a process called backwashing — reversing the flow of water through the filter media to flush accumulated debris out through a waste port to the sewer. Cartridge filters don't backwash; they're cleaned by physically removing and rinsing the cartridge. That difference has meaningful implications for water usage in a desert climate.
Backwash Water Usage — Per Cycle
Each backwash cycle on a sand or DE filter uses a significant volume of water. In Las Vegas, where water conservation is both environmentally important and increasingly regulated, this is a real operating consideration over the life of the filter.
Complete Filter Comparison
| 🟦 Cartridge | 🔵 DE | 🟤 Sand | |
|---|---|---|---|
| Filtration fineness | 10–15 microns | 3–5 microns | 20–40 microns |
| Backwashing required? | No | Yes | Yes |
| Water used to clean | ~0 gallons (rinse only) | 50–100 gal/cycle | 50–100 gal/cycle |
| Cleaning method | Remove & rinse cartridge | Backwash + recharge DE powder | Backwash sand bed |
| Cleaning frequency (Las Vegas) | Every 4–6 months or per pressure gauge | Per pressure gauge; annual grid inspection | Per pressure gauge |
| Media replacement | Cartridge: 24–36 months (LV) | DE powder: each backwash; grids: 5–7 yrs | Sand: every 5–7 years |
| Initial cost | Medium | Medium–High | Lowest |
| Ongoing maintenance effort | Low | Higher | Medium |
| Recommended for Las Vegas? | ✓ Best Choice | ✓ Great if you want finest filtration | Not recommended |
Water Conservation — A Las Vegas-Specific Consideration
In a desert climate where water supply from Lake Mead and the Colorado River system is under sustained pressure, every gallon matters. The Southern Nevada Water Authority has progressively tightened conservation requirements — and residential pool operations are part of that picture.
Cartridge filters, which require no backwashing, have a meaningful advantage in this context over DE and sand filters that discharge 50–100 gallons per cleaning cycle. For new pool builds or filter replacements in Las Vegas, the water savings from a cartridge filter over 10 years of operation are substantial — particularly compared to a sand filter that may require monthly backwashing to maintain performance.
Not Sure What Filter You Have or Need?
We service all three filter types and can help you choose the right upgrade for your pool.