Nitrates 9.9ppm so that's not it. I just watched him for the last 20min because lights are ramping down and it's almost time for him to go to bed. He was swimming around normally and stops at the back wall to pick at a little algae with no nudging. He then went into his cave for a few minutes. Goes in tail first as always, took a dump as always and then came out where the Duncan and Plate Coral are and started to nudge over them. Swam around a little, went to the left back corner and hovered for a few seconds without nudging then came back near his cave hovering over the Duncan and Plate and started to nudge a little. His buoyancy is fine. Can hover with no issue in other areas of the tank and only seems to nudge near his cave when over the Duncan and Plate. He knows when I spot feed the corals that there is food on them and will pick the food from them but I did not feed the corals today or yesterday. I turned off my Vortech's for a few minutes and there was a few pieces of nori that floated off the Vortech guards and he chased the nori down along with the Foxface. His routine did not change with no flow in the tank so flow is not the issue. Lights go off in 15min so I will check him with my blue flashlight to see if he nudges while in his cave. What would be your opinion if he is perfectly fine while in his cave?