Use eco-friendly materials to build the rainwater harvesting system

The rainwater collecting tank should be dark colour to ensure no sunlight can penetrate the material to avoid the growth of algae in the tank

Rainwater collecting tank that can easily clean / remove the mug (sedimentation)

Large capacity of rainwater collecting tank so that it can collect and store more water

Low total cost of installation

Rainwater harvesting system that is easy to install

Apply coating on the galvanized tanks to have them in potable grade and to prevent rusting at any welded seams.

The rainwater collecting tank must not have discharged feed from roof-mounted appliances such as air-conditioners or hot-water systems

Metallic roofs should be avoided as metallic roofs can react with steel tanks and can cause corrosion, making stored water unsafe for drinking and cooking.

Treated wood tiles could emit toxic products, they are also to be avoided in order not to contaminate the water 

The rainwater tanks must be properly sealed as improperly sealed rainwater tanks may become the breeding grounds of mosquitoes. 

Underground tanks are most preferable to avoid mosquitoes contamination as they are dark and keep the water too cool (12.8 C) which is just perfect for killing any mosquito larvae, bacterial and algae growth.

Multi-stages of filtration to avoid contaminant.

Use filters to remove major impurities and leaves  

Implement redundancy system as a back-up plan.

Use minimum complexity in automated system (so that normal technician could overcome if there is any problem occurred)

Implement solar system to produce electricity (environmental friendly)

Avoid using chemical to disinfect microorganism (environmental friendly)

Implement the captured rainwater tank at the top part to reduce the usage of pump (reduce the usage of electricity)

Rainwater harvesting system should as near as possible to the location where we want to use it

Reduce high technology system for the filtration or disinfection process (cost-saving).

Recycle the available equipment (cost-saving)

Use rooftop harvesting system

Use PVC type for the pipeline system (cost-saving)

Connect the harvested water to the toilet flushing system and the extra to fire sprinkler system.

Additionally, collect any clean released water to the rainwater harvesting system to increase the volume of water captured (zero waste)

Provide in-built overflow 

Provide waste water discharge

Large rain collector to collect as much rainwater as possible

Larger pipes to ensure more flow of water