Water for Carnivorous Plants: Tap in Humidity Trays, Pitcher Filling, and Rainwater Storage

Hard tap water is fine in humidity trays (mineral buildup is cosmetic only). Never use it in soil. Filling Nepenthes pitchers is unnecessary but harmless if using distilled water. Mucky rainwater is acceptable unless roof leaches zinc/copper.

Quick Rules

• Soil: Only distilled, rain, RO, or ≤50 ppm TDS water.
• Humidity trays: Tap water OK; clean periodically.
• Pitchers: Don't fill; if you do, use distilled.
• Rainwater: Filter debris; avoid metal roofs. Store in food-grade barrels.

Rainwater Collection Tips

• First-flush diverter removes roof contaminants.
• Opaque containers prevent algae.
• Screen inlets to keep mosquitoes out.

Prioritize soil water purity; everything else is flexible.