Maybe your ph is too low , it's common to start with 5.5 but you need to upgrade the level to 5.8 after 1st week ( rooting ) to makes more nutrients available. Here you have purple stem and purplish leaves on the second node and your leaves are droopy. The droopy leaves could be due to an overwatering , sometimes water input is too important in hydro for a young seedling, maybe you should try to not let the pump on during 24h straight. Concerning the purplish and the pale green it is just because your Ec is too low , in hydro I would already gave 1.2 ec or 0.8 minimum, she needs to eat