I've not kept tigrinus yet, the high price and high juvinile mortality rate plus their sensative nature has always put me off, i'm not rich enough to lose a £300 fish.
From what i understand they are extreemly sensative to water quality when young and even relatively low levels of nitrate in the aquarium is detrimental to them, ammonia and nitrite of course is unthinkable. Husbandry should be similar to that of stingrays with large regular water changes and pleanty of live foods until they can be weened onto frozen
T1karmen has had a few tigs in his time so is probably the best to give advise