Its scary to see rowsley drop 20+% in one day when its one of the popular stock of the period..

What exactly happened? Trading curb.

According to the business times:
SOME six weeks ago, this column warned of the strong likelihood that with the fever in penny stock punting threatening to boil over dangerously, local broking houses faced with rising credit risks or over-exposure to a huge speculative bubble would surely act to protect themselves by imposing trading curbs on many of the stocks.

This has now occurred - over the past few days, at least one large broker is said to have slapped limits on trading on the entire penny sector. Precise details are not known but it is thought that clients' exposure to each non-marginable stock is now limited to $50-100,000 depending on trading limits, and $300,000 in total.

Whatever the specifics, the effect has been painful - ......