Can you keep a goldfish in an opaque glass tank?

It is generally not recommended to keep goldfish in an opaque glass tank. Opaque glass blocks the natural light required for the well-being of goldfish.

Goldfish need proper lighting to regulate their sleep-wake cycle, promote healthy growth, and support their overall metabolism. Without access to natural sunlight or appropriate artificial lighting, goldfish can suffer from health problems, including decreased activity, loss of appetite, and weakened immune systems.

Furthermore, an opaque glass tank limits the owner's ability to observe the goldfish. Goldfish owners should be able to closely monitor their pets for signs of illness or distress and promptly adjust the tank conditions if necessary. An opaque glass tank makes it difficult to observe the goldfish's behavior and appearance, which can delay or prevent proper care and treatment.

Translucent glass can still have a negative impact on a goldfish's ability to see out of their tank. Transparent enclosures, such as clear glass tanks, provide the best visibility and lighting for the fish within.