Brown spots on leaf tips of old growth.

I'm with ezzjaybruh here.... his 29 diaries show he knows what he's talking about!

EC need to get up! I used these nutrients a lot when growing hydrophonics and I have never been under EC 1.0 I always started first week EC 1.0 and up this every week by EC 0.1 till you reach EC 1.8 (EC 1.8 is enough till harvest!!!). I always only used the 3 GHE nutritions with GHE powder pH minus and Dutch tap water. Last week flush and BOEM!!! Harvest big buds every time 😋 The reason your EC stays stable is because she is only using the nutrients thats she needs right now. A lot more N then P or K. So what you measure now is a stable EC but this is all old P and K. When cannabis plants are eating a lot in hydrophinics the pH will go up slightly too because the nutrients are a bit acid compare to the water. So when your pH stays perfectly stable you can see already that she barley eats nutrients. I like to play with the nutrients and always make the solution 5.5 and let it go up a little to 6 and then make it 5.5 again. This way other nutrients become available easier for the plant. Happy Growing! 😋

You are experiencing potassium deficiency. Brown straight tips is potassium deficiency. Brown curling up and in tips is nute burn. Dark green curling down is nitrogen toxicity.