Hi Cai. First of all I really like your layout. I think that it really works and your plants seem to be starting to thrive. I'm not so sure about why your not reaching your 1 ph drop by lights on, but could the high nitrate levels your test kit is detecting, be as a result of the EI dosing you are doing? Don't forget that one of the larger components of the macro fertiliser mix is potassium nitrate, and although I'm not an expert on test kits, I would suspect that this could be causing a reaction with the test kit chemicals as they respond to nitrates. With the co2 and the lack of ph drop, I'm not sure you should worry so much about it, considering that your drop checker is indicating good levels of Co2 when it's measuring the ph of the 'atmosphere' rising from your aquarium water. I'm not a planted tank expert,in fact I am in the first couple of weeks of running my own first high energy tank,but a lot of the advise I have gleaned from speaking to many of the more experienced guys on here,and outside seems to point me towards not getting to wrapped up with the results from water test kits,like the ammonia,nitrite,nitrate and pH etc,but to concentrate more on applying correct EI dosing, lighting (and co2 using the drop checker), and to pay more attention to how the plants respond to changes in these variables,than what the test kits say. On the same note, I also changed my mind on my original intention of using a ph controller to control my solenoid based on this same advice, as I was advised that there are many variables in the aquarium that affect the ph of the water, which can lead to the controller not giving the ideal instructions to the solenoid, in terms of keeping your co2 levels correct and constant. I would be inclined to pay most attention to your drop checker results, and the response of the plants,which seem to indicate that your co2 is correct, and also worry less about the tank cycling parameters, especially as you currently have no fish in there. The tank will definitely cycle when it has a consistent source of ammonia. 🙂