If the ants cause no harm, they are not to be killed. The Prophet salla Allahu alaihi wa salaam prohibited killing ants, bees, hoopoes, and sparrow-hawks (Abu Dawud).  This case only applies when they cause no harm.

Is it totally impermissible to kill ant?

Commentary on Hadeeth | June 18, 2017 3:03 am
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Can i please get the authenticity of this hadees.“If a woman performs the five (prayers), fasts the month (of Ramadan) and obeys her husband, she will enter paradise from any gate she wants.” (Ahmad)
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Is this Hadith authentic? Narrated ‘Ubaadah that the Messenger of Allah said, “Whoever seeks forgiveness for the believing men and believing women, Allah will write for him a good deed for each believing man and believing woman.” (Tabarrani, classed as hasan by Albani) I’m sorry, I don’t have the hadith in Arabic.Only found this online.