Copper Sulfate in Clay Pond: Hardness Matters

Same pond as above. Asks if 24–36 hr exposure kills chara/spores. Treat removed fish for spores?

Hardness Determines Copper Efficacy

High hardness = copper precipitates in <10 minutes. Low hardness = longer active. Must match dose to hardness via chart.

Multiple treatments usually needed. Spot-treat remnants.

Clay Bottom Warning

Copper sulfate creates sterile bottom—beneficial bacteria can't colonize. Chelated copper (Cutrine) is gentler, biodegradable. Use it for retreatments.

Don't treat fish for "spores"—chara spreads via fragments, not fish-borne spores.