A pretty fair summing up of the situation. Sea horses (plus their close relatives - pipefishes, pipehorses etc) have relatively large fry, although there is still quite a range of sizes. The species which need specialised feeding and care (in the Kreisel tanks described in the article) are widely distributed because their fry are so small that they spend a long time drifting in the current: in consequence they are less vulnerable than species with larger fry which may have very limited ranges (such as the Knysna seahorse).
A similar situation occurs with coral reef fishes, the vast majority have planktonic eggs and larvae and are widely distributed. They are not in danger of extinction in the forseeable future, which is just as well because most of these species cannot be reared in captivity. There are a few species whose larvae are not planktonic and have limited ranges - these could be aided by captive breeding - the best example is the Banggai cardinalfish.
Aquarium breeding to reduce the dependence of the trade on wild-caught species is welcome, as the article explains. However the popularity of reef tanks means that the invertebrates of the coral reefs need similar effort. Propagation of corals is making progress, but work could be done on many other groups. I think the collection of 'living rock' (rock from reefs which is colonised by a range of small invertebrates) is a problem.
Alan
