Pentair 188625 FullFloXF FV72 D.E. Pool Filter — 72 sq ft Fiberglass with Built-In Backwash Valve, 2 in — Genuine OEM

The Pentair 188625 FullFloXF FV72 is the larger of the two FullFloXF FV D.E. filters — 72 sq ft of fiberglass grid-style filtration with the backwash valve built into the tank, handling up to 144 GPM on 2 in plumbing.

⚠️ Not the Same as the F72 (188621)

Pentair sells two 72 sq ft FullFloXF D.E. filters and they are easy to confuse — both are 72 sq ft, both are rated 144 GPM, both are grid-style D.E. The differences that matter:

• 188625 FV72 (this one): 2 in plumbing, backwash valve included, 76 in clearance
• 188621 F72: 2.5-3 in plumbing, no valve included (needs 262511 or 410020, bought separately), 92 in clearance

Pentair's F-series manual warns that "failure to use the correct backwash valve could damage the filter cartridges and void the warranty." Match your plumbing size: 2 in takes this filter, 2.5-3 in takes the F72.

FV72 or FV60?

• 188625 FV72 (this one): 72 sq ft, 144 GPM, 76 in vertical clearance
• 188624 FV60: 58 sq ft, 116 GPM, 70 in vertical clearance

Both tanks are 21.5 in across, both run 2 in plumbing, and both take the same 7.2 lb D.E. charge, so the pad footprint is identical. The deciding factor is usually headroom, not price. You need 76 in above this filter to lift the lid and withdraw the grid assembly — six inches more than the FV60. Pentair's installation manual is more conservative still, calling for 7 ft (84 in); if you are planning a new equipment room rather than measuring an existing one, use 84 in.

Sizing by Pool Volume

At an 8-hour turnover the FV72 suits pools up to about 69,120 gallons; at 12 hours, up to 103,680. If you are choosing between the two sizes and have the clearance, this is the one to take: more filter area means longer runs between cleanings, lower head loss and less work for the pump.

Why D.E. Rather Than Sand or Cartridge

Diatomaceous earth coats the grids and filters finer than either sand or cartridge media, down to a few microns. It is what you choose when water clarity is the priority. The trade-offs: D.E. needs recharging after every backwash, and spent D.E. slurry has disposal rules in many jurisdictions — check locally before committing to the technology.

⚠️ Never Run It Without D.E.

Pentair's manual is blunt: "If filter operates without diatomaceous earth (D.E.) for more than 3 minutes, filter elements may be damaged." Recharge with 7.2 lb of D.E. after every backwash before the pump goes back on.

Key Features

• 72 sq ft of D.E. filtration: up to 144 GPM.
• Backwash valve included: a 2 in rotary valve built into the tank, unlike the F72.
• Fiberglass reinforced tank: will not rust or corrode in pool chemistry.
• Finest filtration of the three media types: D.E. traps down to a few microns.
• 2 in plumbing: suits standard residential pad layouts.
• 21.5 in diameter: same footprint as the FV60, so swapping sizes does not change the pad layout.

Specifications

• Part Number: 188625
• Product: FullFloXF FV72 fiberglass D.E. filter, 4000-Series (manual P/N 198287)
• Filter Area: 72 sq ft
• Maximum Flow Rate: 144 GPM
• Plumbing: 2 in
• Filter Diameter: 21.5 in
• Vertical Clearance Required: 76 in minimum (installation manual specifies 84 in)
• Maximum Working Pressure: 50 psi
• D.E. Media Required: 7.2 lb (3.3 kg)
• Turnover, 8 hours: 69,120 gal
• Turnover, 10 hours: 86,400 gal
• Turnover, 12 hours: 103,680 gal
• Valve: Built-in 2 in rotary backwash valve (service parts 178828 assembly, 073370 rotor and seal)
• Tank Material: Fiberglass reinforced polypropylene
• Anchor Clamp Kit: 178840, sold separately, recommended in high-wind and seismic areas
• Smaller Size: FV60, item 188624
• Do Not Confuse With: F72, item 188621, 2.5-3 in plumbing and no valve included
• Brand: Pentair (Genuine OEM)

Installation and Safety

Pentair states "only a qualified plumbing professional should install this filter." Key points from the manual: maximum working pressure is 50 psi; do not pressure test with compressed air; do not connect to a high-pressure or city water supply; open the air relief valve and wait for pressure to reach zero before servicing; keep electrical controls at least 5 ft from the filter; mount on a level concrete slab; support piping independently; and use only PTFE or silicone lubricant on the O-rings, never petroleum-based.

Warranty — Read This Before You Buy Online

Pentair lists filters at a 2-year parts and labour warranty, but its published policy carves out online purchases: "Products purchased from the internet, including Authorized Pentair Online Resellers, receive a one-year parts only warranty from the date of purchase," and "labor is not covered for... internet purchases." The three-year bundle warranty also excludes internet purchases. The internal D.E. grids are classed as consumables at one year.

Frequently Asked Questions

How is this different from the F72, item 188621?

Plumbing size and the valve. Both are 72 sq ft and 144 GPM, but this filter takes 2 in plumbing and includes its backwash valve, while the F72 takes 2.5-3 in and needs a valve bought separately. Pentair warns that fitting the wrong valve can damage the elements and void the warranty.

How much headroom do I actually need?

76 inches above the filter as published, and Pentair's installation manual asks for 84. Use 84 if you are designing a new equipment room. If you cannot clear it, look at the FV60, which needs 70 in.

What is the difference between this and the 188624 FV60?

Area and flow. This filter gives 72 sq ft and 144 GPM against the FV60's 58 sq ft and 116 GPM. Same 21.5 in diameter, same 2 in plumbing, same 7.2 lb D.E. charge.

Does it include the backwash valve?

Yes, a 2 in rotary valve is built into the tank.

How much D.E. does it take?

7.2 lb, roughly 14 one-pound scoops, and it is not included. Recharge after every backwash — running the filter without D.E. for more than three minutes can damage the grids.

How do I size this against my pump?

The filter should be rated at or above your pump's maximum flow. At 144 GPM it comfortably covers residential variable speed pumps at full output, but check your pump curve at your system's actual head rather than its nameplate horsepower.

How does it ship?

As a freight shipment rather than by parcel carrier. Inspect the carton on delivery and note any damage on the carrier paperwork before you sign.

California Proposition 65 Warning: This product can expose you to chemicals known to the State of California to cause cancer and reproductive harm. For more information go to www.P65Warnings.ca.gov.