The Topaz Blue guppy is a distinct and visually striking variety known for its deep blue coloration and often metallic sheen. Here are some key features and care considerations for Topaz Blue guppies:

1. **Coloration**: Topaz Blue guppies exhibit a vibrant blue coloration that can range from light to dark shades. The metallic sheen adds a shimmering effect to their appearance, making them particularly eye-catching.

2. **Size**: Guppies are small fish, typically growing to about 1.5-2.5 inches (3.8-6.3 cm) in length, including their flowing fins.

3. **Water Parameters**: They are adaptable and can thrive in a wide range of water parameters. Topaz Blue guppies prefer slightly alkaline to neutral water with a pH range of 7.0-8.0 and temperatures between 72-82°F (22-28°C).

4. **Tank Setup**: Topaz Blue guppies are active swimmers and appreciate a well-planted aquarium with open swimming areas. Providing floating plants and hiding spots helps reduce stress and provides cover.

5. **Diet**: They are omnivorous and should be fed a varied diet that includes high-quality flake or pellet food, as well as occasional treats like live or frozen foods such as bloodworms or brine shrimp.

6. **Compatibility**: Guppies are generally peaceful fish and can be kept with other small, non-aggressive freshwater fish and invertebrates. However, males can sometimes be territorial towards each other, especially in smaller tanks.

7. **Breeding**: Guppies are prolific breeders under suitable conditions. Females give birth to live young (fry) after a gestation period of about 4-6 weeks. Providing plenty of hiding places for fry helps increase their survival rate.

8. **Care**: Regular maintenance, including water changes and monitoring water quality, is important for the health of Topaz Blue guppies. They are hardy fish but can be sensitive to poor water conditions and fluctuations.

Topaz Blue guppies are prized for their intense blue color and metallic sheen, making them popular choices among aquarists who appreciate visually striking fish. They add vibrancy and elegance to community tanks and are relatively easy to care for and breed. If you have more specific questions about Topaz Blue guppies or guppy care in general, feel free to ask!