Went to HK recently and visit the street filled with aquarium shops. Quite interesting place. Lots of hardware locally designed/made and prices are very good, much cheaper than in SG (I estimate >30% cheaper)

Notice that smaller tanks like 2 to 3 feet square are more popular (maybe due to their space constraints at home) but very well designed. The sump tank is the same size as the main tank (below it) and thus can house a lot of filtering options esp for marine tanks.

The fishes are kept in very cramped conditions though and many of them are in small plastic bags.

A very good visit experience