Ingredient risk record
Erythromycin
Also appears as: erythromycin phosphate
A macrolide antibiotic used against gram-positive bacterial infections and cyanobacteria. Its notable risk in this database is not to livestock but to the filter: Fritz warns that treatment may inhibit nitrifying bacteria, which means an ammonia spike is a realistic side effect of a course.
Source-linked caution for
The evidence is formulation associated. It raises a warning on a product containing this ingredient but never decides the verdict.
“Treatment may inhibit nitrifying bacteria. Monitor ammonia and nitrite levels during treatment.”
manufacturer page · fritzaquatics.com · checked August 16, 2026
The inference only runs one way
A product containing erythromycin gets a warning. But a product without it gets nothing — no clearance, no green tick. Fritz Algae Clean Out contains no copper and is still explicitly unsafe for shrimp and snails, which is why FishyMag will not certify a product as compatible unless the manufacturer says so directly.
Treatments containing erythromycin
Next steps
FishyMag reports what manufacturers say, quoted and linked. It does not diagnose illness or recommend a treatment, and it never infers that a product is safe from the absence of a warning — where no statement exists, it says so.
Formulations change. Always read the label on the bottle in your hand, and contact the manufacturer if your tank contains anything valuable or unusual.