Sand
Pros: natural look, fish enjoy sifting through it, easy on betta fins. Pool filter sand or black aquarium sand works well — never play sand or builder sand (sharp, dirty).
Cons: compacts over time and develops anaerobic dead zones if not stirred. Use Malaysian trumpet snails to keep it loose. Cleaning requires hovering the gravel vacuum just above the surface, not into the sand.
Gravel
Pros: easy to vacuum, holds plants in place, holds beneficial bacteria, classic look. Choose smooth rounded gravel; avoid sharp pieces that injure fins.
Cons: traps food and waste between pebbles. Requires regular gravel vacuuming or detritus builds up.
- ✦Rinse new gravel until water runs clear before adding.
- ✦Use 1-2 inches depth for most setups.
Bare Bottom
Pros: trivial to clean, ideal for breeding tanks and quarantine, prevents anaerobic dead zones entirely. Best for show breeders who do daily water changes.
Cons: looks utilitarian, fish often appear stressed against the bright reflection. Add a dark background and floating plants to compensate.
Aquasoil (Planted)
Pros: feeds plant roots, lowers pH (good for soft-water fish like bettas), supports a thriving planted tank. ADA Amazonia and Fluval Stratum are top choices.
Cons: leaches ammonia for the first 2-4 weeks (cycle the tank empty before adding fish), expensive, breaks down over 2-3 years.