Whats your ORP hang at usually? biggest thing that surprises me is that 11 liters of kalk is a lot for your size of system so its suprising you are having issues with pHI do have several big fish. I have certainly seen plenty of tanks with more though. I don’t feed super heavy. I use hpd and mastic, so not much wast. I feed my corals often, but I would not say a crazy amount.