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Green Slime on Rocks in a Fishless Pond: Bleach or Plants?

A man-made pond (no fish) has green slime on rocks releasing bubbles when lifted. Treated with Aquashade, Cutrine, sludge bacteria. Owner asks about chemical over/underuse.

Two Paths

Option A: Sterile Maintenance (No Life)

Drain, scrub, refill.
Add 1 ppm chlorine (bleach) weekly.
Use pool test kit.
No plants, animals, or organic matter allowed.

Option B: Ecological Balance (Recommended)

Drain, scrub, refill.
Add diverse plants (marginals, floaters, submerged).
Plants outcompete algae for nutrients.
No chemicals needed long-term.

Since it’s fishless, Option A works but is high-maintenance. Option B creates a living, self-regulating feature. The bubbles are oxygen from algal photosynthesis—normal.

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