Couple suggestions just in case - make sure they have a calcium source - if you are feeding a Layer feed then they are already getting it, but if you are feeding something else, like an All Flock for example, you will want to provide free choice oyster shell in a separate dish. At 1.5 years of age it's possible they will start to molt anytime now, meaning the probably won't lay until they are done molting, You can help speed up that process by feeding a higher protein feed (20-22% protein) white they are growing new feathers. Feathers are made of protein, so supplementing what they get in the feed will help them grow their new feathers without depleting their bodies.