This situation is more common among fish friends. First of all, it is necessary to determine whether it is a parasite or not, and it depends on the behavior of fish. If you are restless and anxious to swim and wipe the cylinder, it is a parasite and needs medication to repel insects. If it is not a parasite, it is generally tissue fluid. Oxygen explodes in water, and the water is electrolyzed in many dimensions to keep it clean. It will absorb and dissipate by itself in a month or so.
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