💦 Calplas AFM/P-720 Side Mount Pool Filter – Up to 94,000 Litre Capacity

Professional-grade semi-high bed filtration for large residential and light commercial pools.

📋 Product Overview

The Calplas AFM/P-720 is a high-capacity semi-high bed pool filter engineered for large residential pools and light commercial applications. Featuring an impressive 720mm diameter tank constructed from hand-laid glass fibre reinforced polyester (GRP), this professional-grade filter delivers substantial water processing capability with a generous 0.40 m² filter area.

With double the filter area of the entry-level 520mm model and a robust 900mm filter bed height, the AFM/P-720 handles pools up to 94,000 litres with ease. The extended media depth ensures exceptional contact time between water and filter media, resulting in outstanding water clarity whether using traditional sand or advanced AFM® activated glass media.

Manufactured in Spain by Calplas according to EN 13121-3 European standards, this filter represents the perfect balance between capacity and practicality for demanding pool installations. The steel-reinforced construction, large 305mm service manhole, transparent acrylic lid, and 3″ sight glass make operation and maintenance straightforward. Compatibility with the Besgo automatic backwash valve system offers hands-free filter cleaning for maximum convenience.

🌟 Key Features

• ✅ Semi-High Bed Design – 900mm filter bed height delivers superior contact time for exceptional filtration performance
• ✅ Substantial Filter Area – 0.40 m² surface area provides double the capacity of the 520mm model
• ✅ GRP Construction – Hand-laid glass fibre reinforced polyester ensures absolute watertightness and corrosion resistance
• ✅ Steel Reinforcement – Additional steel at high-stress points for exceptional long-term durability
• ✅ AFM® Optimised Diffuser – Special diffuser prevents crater formation for ideal water distribution across the filter bed
• ✅ Large Service Manhole – ø 305mm access with transparent acrylic cover for easy media loading and inspection
• ✅ 3″ Sight Glass – Large sight glass for clear backwash water monitoring
• ✅ Pressure Gauge Included – Factory-fitted gauge for accurate filter condition monitoring
• ✅ Drain Plug & Vent – Complete with all essential fittings for installation and winterisation
• ✅ Besgo Valve Compatible – Works with automatic or manual Besgo backwash valve systems (sold separately)
• ✅ EN 13121-3 Certified – Manufactured to European pressure vessel standards
• ✅ 5-Year Tank Warranty – Comprehensive manufacturer warranty for complete peace of mind

🔩 Technical Specifications

Specification	Value
Filter Type	Semi-High Bed Sand/AFM Filter
Tank Diameter	720 mm
Filter Area	0.40 m²
Filter Bed Height	900 mm
Flow Rate (Standard @ 30 m³/h/m²)	11.7 m³/h
Flow Rate (Backwash @ 50 m³/h/m²)	19.5 m³/h
Pool Capacity (6-hour turnover)	Up to 70,200 litres
Pool Capacity (8-hour turnover)	Up to 93,600 litres
Inlet/Outlet Connections	2″ Female Thread (F”)
Tank Height	1440 mm
Distance from Ground	420 mm
Connection Spacing	190 mm
Filter Opening at Top	ø 190 mm
Manhole Diameter	ø 305 mm
Sight Glass Size	3″
Maximum Operating Pressure	2.5 bar
Test Pressure	3.75 bar
Maximum Temperature	40°C
Tank Material	GRP (Glass Fibre Reinforced Polyester)
Tank Colour	Blue RAL 5015 (White available on request)
Weight (Empty)	88 kg
Certification	EN 13121-3
Warranty	5 Years (Tank)

📐 Pool Sizing Guide

The AFM/P-720 is engineered for optimal performance with pools requiring a complete water turnover every 6-8 hours. With an impressive standard flow rate of 11.7 m³/h, this filter delivers reliable filtration for large residential and light commercial pools.

Sizing Formula:

Required Flow Rate (m³/h) = Pool Volume (m³) ÷ Turnover Time (hours)

Pool Size Compatibility:

Pool Type	Volume Range	Suitability
🏠 Large above-ground	40,000-60,000 L	✅ Excellent – fast turnover rates
🏊 Medium in-ground	50,000-70,000 L	✅ Ideal – optimal 6-hour turnover
🏊 Large in-ground	70,000-94,000 L	✅ Good – 8-hour turnover achieved
🏊 Extra large in-ground	80,000-94,000 L	✅ Suitable – reliable performance
🏢 Small commercial	Up to 70,000 L	✅ Excellent with professional setup
🏢 Medium commercial	70,000-94,000 L	✅ Good with 8-hour turnover
🏊 Very large pools	95,000+ L	⚠️ Consider AFM/P-840 or larger model

This Filter:

📍 Standard Flow Rate: 11.7 m³/h
📍 Backwash Flow Rate: 19.5 m³/h  
📍 Optimal for pools up to: 70,200 litres (6-hour turnover)
📍 Maximum for pools up to: 93,600 litres (8-hour turnover)

⚙️ Installation Requirements

Plumbing Connections:

Requirement	Specification
Inlet Connection	2″ Female Thread (F”)
Outlet Connection	2″ Female Thread (F”)
Valve Position	Side Mount
Connection Spacing	190 mm centre-to-centre

Physical Installation:

Requirement	Details
Base	Solid, level concrete pad required
Total Height	1440 mm
Distance from Ground to Connections	420 mm
Clearance Above	Minimum 500 mm for lid removal and media access
Clearance Around	Minimum 700 mm for maintenance access
Weight Consideration	88 kg empty – ensure adequate base support

Pump Compatibility:

⚠️ Filter must be matched with an appropriate pump for optimal performance.
✅ Recommended pump flow rate: 9 - 11.7 m³/h (standard filtration)
✅ Backwash capable pump: Up to 19.5 m³/h
❌ Pump must not exceed filter's maximum flow rate of 19.5 m³/h

Valve Requirements:

The AFM/P-720 is designed for use with the Besgo automatic backwash valve system (available in automatic or manual versions). A coupling set is required and sold separately. The Besgo valve mounts directly to the filter or can be wall-mounted for flexible installation options.

🛠️ Maintenance Guide

Routine Maintenance Schedule:

Task	Frequency	Method
Check pressure gauge	Weekly	Normal operating range: 0.8-1.5 bar
Backwash filter	When pressure rises 0.5-1 bar above clean baseline	Run until sight glass shows clear water
Rinse after backwash	After each backwash	30-60 seconds to settle media
Inspect seals and gaskets	Seasonally	Replace if worn or cracked
Check media level	Annually	Top up if below recommended level
Full media replacement	Every 5-7 years (sand) or 10+ years (AFM®)	Replace completely

Pressure Gauge Guide:

📊 Clean filter baseline: 0.8 - 1.0 bar (typical)
📊 Backwash required: When pressure rises 0.5 - 1.0 bar above baseline
📊 Maximum operating pressure: 2.5 bar
⚠️ If pressure exceeds 2.5 bar, stop pump immediately and investigate

Winterisation (UK Climate):

For UK pool owners, proper winterisation is essential to prevent frost damage:

• Fully drain the filter tank using the drain plug
• Remove and safely store the drain plug
• Leave all valves in open position to allow any residual water to drain
• Cover the filter or store in a frost-free location if possible
• Never leave water standing in the filter during freezing conditions
• Inspect all seals before recommissioning in spring

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🪨 Filter Media Information

Media Capacity Requirements:

Media Type	Quantity Required
Sand/Gravel (25 kg bags)	10 bags Grade 1 + 10 bags Grade 2
AFM® Glass Media (21 kg bags)	11 bags AFM Grade 1 + 11 bags AFM Grade 2

Compatible Media Comparison:

Media Type	Filtration Rating	Lifespan	Key Benefits
Silica Sand	20-40 microns	5-7 years	Economical, widely available
AFM® Glass Media	Down to 1 micron*	10-15+ years	Superior clarity, self-sterilising, reduces chlorine demand
ZeoSand	3-5 microns	5 years	Enhanced clarity, ammonia reduction

*With proper flocculation

Why Choose AFM® Activated Filter Media:

AFM® (Activated Filter Media) is specifically optimised for this filter and offers significant advantages over traditional sand:

• Filters particles down to 1 micron (compared to 20-40 microns with sand)
• Self-sterilising surface prevents bacterial biofilm growth
• Reduces chlorine consumption by up to 50%
• Requires 50% less backwash water
• Maintains consistent performance for 10-15+ years
• Bio-resistant – eliminates trichloramine and chlorine smell
• NSF/ANSI certified for pools and drinking water

Signs Your Media Needs Replacing:

• Poor water clarity despite correct chemical balance
• Increasingly short filter cycles between backwashes
• Cloudy water returning to pool after filtration
• Media visible in pool (indicates lateral damage)
• Filter pressure consistently higher than normal even after backwash

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✨ Filtration Performance

Performance Metric	Value
Filter Area	0.40 m²
Filter Bed Height	900 mm
Standard Flow Rate	11.7 m³/h @ 30 m³/h/m²
Backwash Flow Rate	19.5 m³/h @ 50 m³/h/m²

Micron Rating Guide:

Rating	What It Removes
40+ microns	Visible debris, leaves, large particles
20-40 microns	Sand, dirt, visible particles (typical sand filtration)
10-20 microns	Fine particles, some algae spores
5-10 microns	Very fine particles, most algae
1-5 microns	Ultra-fine particles, bacteria (achievable with AFM®)

The AFM/P-720’s semi-high bed design with 900mm media depth provides exceptional contact time, enhancing both mechanical filtration and flocculation processes for superior water clarity.

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🔧 Besgo Valve Functions

The Calplas AFM/P-720 is designed for use with the Besgo automatic backwash valve system, offering simplified operation compared to traditional multiport valves:

Function	Description
Filter	Normal filtration mode – water flows through media bed
Backwash	Reverse flow cleans media – automated switching available
Rinse	Settles media after backwash (on applicable models)

Besgo Valve Advantages:

• ✅ Automatic backwash capability with timer control
• ✅ No need to stop pump during valve operation
• ✅ Fail-safe design returns to filter mode on power failure
• ✅ Operates in under 2 seconds
• ✅ Silent operation with no pressure hammer
• ✅ Low pressure loss for efficient backwashing
• ✅ Wall or filter-mounted installation options

💡 Note: The Besgo valve and coupling set are sold separately. Contact Parts4Tubs for compatible options.

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🎯 Ideal Applications

Application	Pool Size	Suitability
🏊 Large in-ground pools	60,000-94,000 L	✅ Excellent choice
🏠 Large above-ground pools	50,000-70,000 L	✅ Generous capacity
🏡 Luxury residential pools	Up to 80,000 L	✅ Ideal for demanding installations
🏢 Small commercial pools	Up to 70,000 L	✅ Professional performance
🏢 Holiday let pools	Up to 80,000 L	✅ Reliable for high-use situations
🏨 Hotel/B&B pools	Up to 70,000 L	✅ With professional valve setup

❓ Frequently Asked Questions

Q: What size pool will this filter handle? A: The AFM/P-720 is suitable for pools up to 93,600 litres with an 8-hour turnover time. For optimal 6-hour turnover, it’s ideal for pools up to 70,200 litres with its 11.7 m³/h flow rate.

Q: How often do I need to backwash? A: Backwash when the pressure gauge reads 0.5-1 bar above the clean baseline reading. This is typically every 1-2 weeks during swimming season, but varies based on pool usage and debris load.

Q: What filter media should I use? A: The filter is compatible with silica sand or AFM® glass media. For optimal performance, we recommend AFM® Activated Filter Media which provides filtration down to 1 micron and lasts 10+ years. Sand capacity is approximately 500 kg (10+10 bags of 25kg). AFM® capacity is 22 bags of 21 kg (11 bags Grade 1 + 11 bags Grade 2).

Q: How long does filter media last? A: Silica sand typically lasts 5-7 years before requiring replacement. AFM® glass media maintains performance for 10-15+ years and is self-sterilising, eliminating biofilm buildup.

Q: What pump do I need? A: Match with a pump delivering 9-11.7 m³/h for standard filtration. Ensure the pump can provide up to 19.5 m³/h for effective backwashing. Never exceed the filter’s maximum flow rate.

Q: Is a multiport valve included? A: No, the valve is sold separately. This filter is designed for use with the Besgo automatic backwash valve system (manual or automatic versions available). A coupling set is also required.

Q: How does this compare to smaller models? A: The AFM/P-720 offers double the filter area of the 520 model (0.40 m² vs 0.20 m²) and 33% more than the 640 model (0.40 m² vs 0.30 m²). It handles pools up to 94,000L compared to 48,000L (520) or 74,000L (640).

Q: What warranty is included? A: The Calplas AFM/P-720 comes with a 5-year tank warranty. Contact Parts4Tubs for full warranty terms and conditions.

Q: Is this suitable for commercial use? A: Yes, the AFM/P-720 is suitable for small commercial pools, holiday lets, and B&B installations up to approximately 70,000 litres with a 6-hour turnover. For larger commercial applications, consider the AFM/P-840 or AFM/P-960.

📥 Downloads & Resources

📄 Calplas AFM/P Series Technical Datasheet – Complete specifications for all AFM/P models

🏆 Why Choose the Calplas AFM/P-720

• ✅ High Capacity – 0.40 m² filter area handles pools up to 94,000 litres
• ✅ Premium Spanish Engineering – Over 50 years of filter manufacturing expertise from Calplas
• ✅ Superior Build Quality – Hand-laid GRP construction with steel reinforcement
• ✅ Outstanding Filtration – 900mm semi-high bed provides extended contact time for crystal clear water
• ✅ AFM® Optimised – Special diffuser designed specifically for activated glass media performance
• ✅ Easy Maintenance – Large 305mm manhole and 3″ sight glass for simple monitoring and servicing
• ✅ Future-Proof Design – Compatible with Besgo automatic backwash for hands-free operation
• ✅ Proven Reliability – EN 13121-3 certified with 5-year tank warranty
• ✅ Versatile Application – Suitable for large residential and light commercial installations

🤝 Why Buy from Parts4Tubs

• ✅ UK-based company with local customer support
• ✅ Fast UK delivery on all orders
• ✅ Expert advice from pool and spa specialists
• ✅ Competitive pricing on all Calplas products
• ✅ Full warranty support and after-sales service
• ✅ Easy returns within 30 days
• ✅ Compatible filter media, pumps, and spare parts available
• ✅ Besgo valves and coupling sets in stock

⭐ Summary

The Calplas AFM/P-720 Side Mount Filter delivers professional-grade filtration for large residential pools and light commercial installations up to 94,000 litres. With its substantial 720mm GRP tank and 0.40 m² filter area, this Spanish-engineered filter provides double the capacity of the 520mm model whilst maintaining the same outstanding build quality. The 900mm semi-high bed design ensures exceptional water clarity when paired with AFM® activated glass media. Complete with large 305mm service manhole, 3″ sight glass, and Besgo automatic backwash compatibility, the AFM/P-720 is the ideal choice for demanding pool installations requiring powerful, reliable filtration backed by a 5-year tank warranty.

Order your Calplas AFM/P-720 today and enjoy crystal clear pool water all season long!