To be perfectly honest, it's pretty small for 5wks. Stear clear of decomposing material, especially indoors. Indoor you're going to want more stable nutrients. MG is awful. Get rid of it. There's a reason it's so cheap. If you can, bump your hours of daylight up to 16-18. Stick with 18 if they're staying indoors forever. It's stunted but healthy! Give it some good potting soil, and check your ph and you'll be off to the races!