Sayyiduna Ali (may Allah be pleased with him) said that I used to suffer from excessive discharge of madhiy. I asked the Prophet (peace and blessings be upon him) about its ruling, so he said: "Ghusl is obligatory due to semen, and for madhiy only wudu is obligatory."
Hadith Referenceمسند احمد / مسند الخلفاء الراشدين / 662
Hadith Gradingحکم دارالسلام:حديث صحيح، وهذا إسناد ضعيف لضعف يزيد بن أبى زياد الهاشمي