His new coach there was Stefaan Maene, an ex-Olympic swimmer that participated in the 1992 Summer Olympics in Barcelona.

In 2005 Greg Planckaert became the club's new head coach and took Decaesstecker to the World Championships in Durban, South Africa in 2006.

His studies have led him to participate in the 2006 elections for city council in his hometown of Kortemark, as a candidate for the Flemish Liberals and Democrats (VLD) and as a member of the majority.

The first International Paralympic competition Decaesstecker went to was the European Championships in Brauwnschweig, Germany in 1999.

Again he made the finals in the 100 m backstroke, 400 m freestyle, 200 m individual medley and won the bronze medal on 100 m breaststroke.

At the next Paralympic Swimming World Championships in Durban, South Africa in 2006 Decaesstecker was again going for the medal.