Many of you may already seen my thread about ph flucuating. I thought it was the probe. So i bought another. Same thing. So i assumed it was the sl1. So i trashed the reef keeper and bought myself a apex jr. Installes and ready to use. Next day i looked on my graph and it was the same thing! What can actually cause my ph to drop from 7.8 at night to 8.5 before lights turning off?? My ca.alk.mg is all perfect in line. My room is well ventilated. Also can a bad batch if salt mess up my ph? Thats the only thing i changed when i moved. All od my sps coral are retracting and getting dull . Can there be elecrtical that causes ph to do this? I know co2 plays a part in this. But my skimmer is rated for 60g and i have it for a 30g. And its also vented in my room. and no i cannot put a fuge. Help is needed please..