How often should I change the water for my Betta fish to ensure their optimal health and well-being? Is there a specific frequency that is universally accepted among aquarists, or does it vary based on the tank size, water quality, and the number of fish present? Considering the delicate nature of Betta fish, can the quality of the water alone dictate how frequently changes should occur? Should I factor in additional elements such as filtration, temperature fluctuations, or the presence of uneaten food and waste? Furthermore, is there a difference in the required maintenance for a planted tank versus a bare-bottom aquarium? How does the ammonia level in the water correlate with the necessity for water changes, and what role does regular testing play in this process? Would a partial change suffice, or is a complete water change advisable in certain circumstances? What signs should I look for to determine if my Betta is in distress due to water conditions?