As much as they can eat in 5 minutes. A fish's stomach is as big as his eyes, with a few exceptions - those in the cat fish family, they have no rib cage surrounding their bellies.

Change water at least once a week to avoid new tank cycle and bacterial infections, ie: fungus. Use a water conditioner such as Splendid Betta - Complete Water Conditioner and Splendid Betta - BettaFix Remedy for fungus, etc.

Siphon one third from the bottom every three weeks. If you live in an area with chloramines add chloramine remove, it works instantly. Trace elements are recommended.

Yes! Taste buds are concentrated in the mouth, and in the skin surrounding the mouth including the barbels of loaches and catfish.

Structural diversity is perhaps greatest among tropical fish. In some cases males and females exhibit what's called external sexual dimorphism. For instance, females may have more rounded bodies and longer fins than males. There are also some external secondary sex characteristics such as vivid coloration in males, small raised dumps on the male's head and mouth in some species, rounding of the female abdomen, female are generally larger than males, and males of some live bearing species end up with modified anal fins, called gonadopodia, which help internal egg fertilization.

The sex of a turtle is determined by the temperature at which the egg is incubated.

• Warm temperature - females
• Cool temperature - males
• Moderate temperature - mixed clutch

They can live to be 100 years of age or more.

Guppies are a peaceful fish that like neutral to slightly alkaline waters (ph 7.0). They tolerate soft water well, but prefer it to be medium-hard. Females are larger and less colorful than males. They tolerate a relatively wide temperature range of 60-90 degrees F, but prefer a temperature range of 72-82 degrees F (22-28 degrees C). They accept a wide variety of feed, are good in community tanks, and like planted environments. They are brightly colored fish, and are enjoyable to keep.