I have grown this strain many times in all mediums and tend to find it flourishes on the lower EC levels, hard to judge as it depends on many variables as light intensity/environment as I am sure you know but they look a picture of health in the photos so I wouldn’t change much and increase feed level in small doses as this strain is very easy to over fert especially on nitrogen as I have done myself which reduced yield quite considerably.
I have about 4 or 5 runtz muffin diaries so feel free to check my feed levels and any other questions feel free to ask👍