Hi, First timer here. On Day 37 from seed, topped at 3rd node 4 days ago, PH 6.0, PPM 540, water temp 23 degrees Celsius, RH 50%, Room temp 23-30 Celsius. From what I've read so far it looks like it could be PH Fluctuations but PH hasn't gone below 5.7 or above 6.3 for about the past 2 weeks...