Note: These filters are manufactured in Brazil and are one of our most popular products. We have been encountering inventory delays and are working to resolve the issue — more are coming soon.
The Most Innovative Rainwater Pre-Filter on the Market
Developed in Brazil, we worked directly with the manufacturer to import the Monjolin Mini because of its ingenuity and effectiveness. This is the only pre-filter to filter down to 136 microns while sending leaves and debris straight through to the discharge point — making it genuinely low maintenance. The access panel on both sides gives you the flexibility to mount it discharging debris to the right or left.
Recommended for homes and cabins with 1–4 downspouts feeding a cistern used for drinking water. One filter per downspout. Bulk discounts available: save $20.00 per unit when you buy 3 or more.
Key Features
- Filtering capacity: 8 L/s (127 gpm)
- Mesh opening: 136 microns
- Dimensions: 36.0 cm W × 46.5 cm H × 17.8 cm D (14.2" × 18.3" × 7")
- Rainwater inlet: 114.3–101.6 mm (4.5"–4.0")
- Filtered water outlet: 101.6 mm (4.0")
- Discharge outlet: 101.6 mm (4.0")
- Color: White (paintable fiberglass) — also available in Matte Black
- Material: 100% recyclable plastic
- Installation difficulty: 2 out of 10
- Maintenance frequency: Every 6–12 months depending on tree coverage
Works great in all climates and on all terrain types. Because it mounts above ground, it's compatible with virtually any rainwater system configuration. It's our favorite, most user-friendly, most effective pre-filter.
To order replacement filter elements: Monjolin Mini Replacement Filter Element
Monjolin Mini Pre-Filter Overview
Monjolin Mini Installation
Monjolin Mini Filter Performance
Monjolin Mini in Action
Monjolin Mini System Setup
