The quality of the water is the main problem if you try to hatch eggs without the father.
In nature, Paros live in running water. Additionally, the father makes a soft water-change-effect by his fins. This all is missing in a jar. There will be great problems of funghus and bacteria if you do not change the water. Mostly, this is not successful without picking out bad eggs in a daily turn und using funghicids and frequent (= daily) water changes.