I suggest getting a good filter like Culligan and put it indoor (under sink). It can filter out those VOC gasses inside the water, something other filter can't

CLick below to see the Culligan filter.
http://www.lelong.com.my/culligan-ic-ez-4-...7-01-Sale-I.htm

yup 3M is very small and does not require backwash, very suitable for condo. However, before installation, nd to check with management as well. For more info, jus drop by our showroom
https://www.facebook.com/builders.hardware/info

without the outdoor filter the indoor one will get clogged fast unless ur water is clean. Checked culligan and it seems to be similar to 3M AP Easy Complete but at a sligtly lower price. However, the undermount installation tap is not included (usually cost RM 80), replacement cartridge price is ard rm 150+ more expensive than 3M and capacity is 500gal while 3M is 750gal (50% more)