- It is a good practice and important to take a few moments to look at your aquarium tank everyday.
- Did every fish get to eat something today? Some may be picky about the type of food they will eat, or some are bullied during meal times.
- Are there any fishes in the tank behaving or swimming abnormally? It takes some experience to determine what is "normal" for each type of fish.
- Does the fishes in the tank appear to get along? There can be compatibility problems even for a tank that is full with so called "community fishes" when living in the same environment. Some fishes may show signs of dominance or aggressive behaviour.
- Observe the water in the tank to ensure that it is not cloudy; does not have foul odour, and that nothing out of the norm is floating around
- Plants - If you keep live plants in your fish tank, be sure that any dead leaves are removed and excess plant growth is trimmed.
- Algae - Using an algae magnet or scraper, clean off algae from surfaces of the fish tank as well as decorations
- Lastly, do you observe any fishes with torn fins, discolouration, white spots, red blotches or other signs of disease?