You need less light, at least for a bit... the nodes are too tightly backed and may have temporarily stunted gowth. Also, it needs fertilizer... it's clearly hungry.
no info given to help you on fertilizers... all i can say is ratio, concentration and pH are all equally important factors.
irrigation practices.. always irrigate entirety of media... if soilless, you want 10% or more runoff waste (down drain o toss outside). if soil, you still want to be crtain you don't leave dry pockets repeatedly as these zones will be prone to mineral buildup and all sorts of pH swings etc... generally unhealthy for roots. But, minimal runoff is goal here since oyu don't want to waste the nutrient charge of your soil or your fertilizers are microbe-dependent etc and need time before they are plant available.. can't be washing that away with runoff and think it's optimal, right?
until you learn more keep it simple... wait for pot to be very light before irrigating again. in soil, top 1" dries and feel weight of pot.. good indicator. with coco, wait for superficial layer to dry on top and feel weight for indicator... if you always water at same weight of the pot, it'll require a simila volume of water to accomplish the task... *you dont' pick volume.. you give what is necessay to achieve what is described in previous paragraph.