Hi zheilwane I looking for outdoor water filter for condo in KL. Management told me can only install inside my parcel, can suggest which is best for me?

Based on what I researched, here is the sum up of pros and cons for both filter type.

Membrane type filter
Pros
- Smaller in size
- Filtration better than sand filter
Cons
- Initial cost higher
- Maintenance cost higher in long term
- Might affect the house water pressure
- Certain people said it might filter away the mineral that our body need

Sand type filter
Pros
- Lower initial cost
- Lower maintenance cost
- Less likely to mess up the water pressure
Cons
- Bulky
- Troublesome as need to do backwash periodically
- Will need to do extra piping for the backwash water to flow into drain (if there is no drain near your main switch)

Wall hack is a must as our pipe is inside the wall. I will recommend membrane type for condo user like us as the sand filter vessel is really big. But I myself will be choosing sand type filter as my renovation haven't start and I'll be able to customise a cabinet to hide it.