Crystal White 100 watt LED Spliff Soil

Please look at this , I water once a week , ph water , nothing else , not 15 times a day a@10 ml , soak it right through then leave, it I noticed the leaves going paler , I’ll be honest it was just some dry soil I found , so I repotted into a 25 litre round pot with Plant Magic ( black bag 50 l ) soil - I poured 10 litres of ph water (6.5) and caught the excess. ( Runoff)