water treatment

Hi, I have a 13l tank unplanted with one Betta. It is heated to 26.5 degrees Celsius, pH 7.1, ammonia 1.0, nitrite 0, Nitrate 0. I had to do a big clean of the tank after only having it for 4 weeks as the live plant that I bought started dying and left a huge mess. The tank has only been...

My aquarium is falling apart. I am a beginner at keeping an aquarium. I started off with two goldfish that I won at the fair, which turned into one goldfish because the other died because the tank was too small. Last month the goldfish started getting aggressive because the tank was too small...