Can I take another wife without telling my first wife?

Through lawful channels, no, because the court will summon the existing wife to attend the hearing of the application. The only way to keep it secret is to marry without permission, which is an offence under the state Enactment (for example Act 303, s.123). It also leaves the second wife and children without clear documents. Morally, hiding a marriage often leads to neglect of the rotation and maintenance, and to greater conflict when it comes to light. Islam encourages announcing a marriage and demands justice. Discuss honestly, and get counselling help if needed. See secret polygyny.