The amount of food should be one flake per fish, twice a day.
As for keeping it clean, vacuum the gravel once a week, remove 25% of the water, and then put new water into the tank with conditioner.
The brown particles you are seeing sound like diatoms. New tanks go through different phases over the first 4-6 months. You treat the diatoms like algae, and when you do your partial water change, just clean the inside of the tank glass with a soft cloth. Just wipe it up and down. If you get on a regular routine, the tank will look gorgeous once it has established itself, but it will take some time, and you will always have times when algae is present.
Stores maintain perfect looking tanks because they have clerks to work on them throughout the day, all day long.
answered 4 months, 4 weeks ago
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