The foliage in the photos looks like they were subject to some type of past environmental damage. Overall the plant looks good and you will have to focus on proper care. This plant does not adapt well indoors. It likes bright light indoors and supplemental lighting if possible.
Provide at least four hours a day of direct sunlight.  Normal room temperatures are fine and for increased humidity stand on trays of damp pebbles and mist spray occasionally.  While plants are actively growing, water moderately, allowing the top inch of the mixture to dry out between waterings.  In any resting period water only enough to keep the mixture from drying out.  In the active growth period (not now) give a high potassium tomato type fertilizer every two weeks.  Move plants into one container size larger every spring until maximum pot size has been reached.  Then top dress with an annual top dressing of fresh potting mixture.  Make sure the container has holes for drainage. Place outdoors in bright light during the summer. See the attached link for more information http://aggie-horticulture.tamu.edu/patiocitrus/Calamondin.html
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