The question I have is this I realize that the PH in our tanks drops at night which mine is doing perfectly well. But in the morning when I give the tank the quick check before work it's down to around 8.13 - 8.15 and at night after I get home from work and the lights have been running during the day it's only up to 8.17 - 8.18. I'm using ESV every other day right now because I have no load on the tank I'm in the forth week of the cycle and all my levels test good as far as ammonia, nitrite and nitrate my temp is 78 degrees and my SG 1.024. After I add the ESV my PH goes up to 8.27 - 8.28 This is happening every day for the last week. Do I need to give the tank more time to settle in or do i need to start using a buffer ? Oh my Calcium is at 350 and my Alk or DKH is at 9.3 Still a bit low on both fronts.