Aruba in March equals some of the best Wahoo fishing around. I have fished in Aruba about a dozen times and depending on the time of year I have had Yellowfin Tuna, Mahi, Wahoo, Sailfish, Blue Marilin, Albacore Tuna, and Kingfsh. March is usually great for Wahoo, it is commom to see 6-10 fish in a half day. They start trolling about 10 minutes out of the harbor. If the weather is good they will take you to the other side of the island. I have always fished with Teaser Charters. They are a local family with two 35' Bertrams fully rigged. In August of 07 I had a 250lb Blue Marlin. The rates usually run about $300 for a half day. They also have a web site.
www.teasercharters.com