No, this is a myth. Fish come in a variety of different shapes and sizes and the best practice is to give your fish ample space to swim from end to end. 

We recommend 1 Litre of water in the aquarium = 1cm of fish (without including the tail)Litre of water in the aquarium = Length(cm) x Width(cm) x Height(cm) / 1000

The best practice is to feed once to twice daily. feed no more than the fish will consume completely in five to ten minutes

A healthy tank should have at least once a week water change.You should do 30 - 50% water change per sessionHow to change water pdf (provide link)

Filter wool should be wash to weekly if it is easy enough for you to remove, if not it should be wash at least once a month

You should check the furniture if it is able to withstand the weight also the top if it is made of sturdy material like solid wood or marble etc.The Top should not bend when heavy items are put on the top. A small aquarium can easily weight 20kg

A constant 5 - 8 hours of light is enough for the fishes and plants. Long hours of lights will encourage algae growth which is not what we want

Algae usually grow because of high waste level in the aquarium and strong intensity/ long hours of lighting. Reducing the lighting intensity or duration will slow down the growth of algae. To stop and prevent algae from growing, water change and cleaning of filters should be done.For more  info, do check out our video on this.

With proper cleaning, some are able to use, but it will be better if you get your rock from a fish store.

Water cloudy occur because you have a overload of waste in the aquarium
1. Usually because you overcrowded your aquarium with fishes.
2 You just started your aquarium and already introduced 100% capacity of fishes into the aquarium. One should only add in 30% of the capacity of fishes into the aquarium at one time. Introduce on the timeline of 7th days, 21st day, 42nd days.
3. You just change a brand new filtration system and you did not use your old filter media but a brand new filter media. This will take out all the beneficial bacteria in the aquarium which are there to help to break down waste in the aquarium.
4. You wash your filter system with tap water instead of aquarium water. The chlorine in the tap water will kill all the beneficial bacteria in the filter media that should be there to help to break down the waste in the aquarium.

You will find glass tank more common in Singapore, both have their pros and cons.We usually recommend glass tank as scratches is the utmost importance for long use.

An aquarium takes at least 21 days to finish cycling, but we do recommend adding some fishes on the 7th day to increase the efficiency of cycling the aquarium

A constant temperature of +- 1 is more important. fluctuating temperatures cause more harm to the fish. for the recommended temperature for tropical fish is 25degree - 29 degree

Go for The largest you can afford to get. large tanks are often easier to maintain than small tanks. You are allow to make mistake for big tank compare to smaller one