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MedZyme Liquid Pond Bacteria
The deadly bacteria behind koi ulcers — Aeromonas and Pseudomonas — live in every pond and attack stressed fish. MedZyme fights them biologically: it floods the pond with hungry beneficial bacteria that eat the same nutrients, starving the bad bacteria down to levels that can't harm your fish. It's a preventative, not a chemical.
Out-competes bad bacteria
Starves ulcer-causing Aeromonas & Pseudomonas of the nutrients they need.
Ultra-concentrated
760 million beneficial bacteria per mL — far more than typical “zyme” products.
Cold-water active
Works down to 40°F — ideal for early spring and late fall.
Totally safe
No chemicals or antibiotics; safe for filters, plants, pets and wildlife.
| Size | Treats |
|---|---|
| 16 oz | 48,000 gallons |
| 1 gallon (with pump) | 384,000 gallons |
- Dose regularly (about every two weeks) through the season as a preventative.
- Uses ~33% less at water temps of 68°F and below.
- Add near good circulation for even distribution.
- Store up to 2 years at room temp, or 3 years refrigerated.
Part of the Aqua Meds koi-health line. Targeted formulas for parasites, water quality & pond biology.
Shop all Aqua Meds →

