At 25c your RH should be between 70 and 72%, that a start...You're VPD is very important, you should download Tent Buddy on your phone and it has a PAR calculator and DLI calculator which is light intensity and length of light time and these are very important as well which is what my issue was when my leaves turn the same way, if you adjust those within 24 hours you'll notice a difference, trouble shoot the rest by making sure your VPD is well within the range .80 to .95 and if that doesn't work make sure you're plants are pots are dry and light to the touch before watering and there's calculators online for size of pot to water ratio..