The question regarding the status of a hadith often requires a nuanced explanation. In summary, a significant group of scholars, including Imam An-Nawawi, hold the view that weak hadiths can be accepted and used as a basis for performing good deeds (Fada'il A'mal), provided certain conditions are met.

However, it's generally advisable to prioritise more reliably authenticated supplications. An alternative supplication that you can recite when breaking your fast is:

ذَهَبَ الظَّمَأُ وَ ابْتَلَّتِ الْعُرُوقُ، وَ ثَبَتَ الأجْرُ إنْ شَاءَ اللَّهُ

Transliteration: ""Dhahaba al-zama'u wa btallati al-'urooqu, wa thabata al-ajru in sha'a Allah.""

Meaning: "Thirst has been quenched, the veins have been moistened, and the reward is confirmed, if Allah wills."

This supplication was recited by Prophet Muhammad (peace be upon him), as narrated by Abu Dawud, and is classified as a hadith hasan (good). The use of authenticated supplications like this one provides greater assurance in one's acts of worship.

It's worth noting that while scholars may accept weak hadiths for encouraging good deeds, when it comes to establishing religious rulings or practices, stronger, more reliably authenticated hadiths are preferred.