yesterday i happened to go to 坑口 and surprisingly there's a fish store call "Aqua Store" 溪水旁水族店 which is in "Nam Fung Plaza" across from MTR of 坑口, pretty convenient.
the store size can't compare with FS ga la..but you can find almost everything, the boss is nice. we had a great chat...it has a very nice big display tank, i guess people who live around that area should have gone there, but if you are not notice, you should try to go. coz if you don't come out to FS that often, that store is very nice, i mean, u can get almost anything and it's not expensive at all...
his website is:
www.aquastore.com.hk
just wanna share this, coz i don't go there often, only went twice in my life and i don't live in that area...

cheers!