I will be out of town for the holidays for about 3 weeks. My brother will be incharge of my tank, but he will only feed and measure salinity/topoff. Over the past 2 weeks i did two 50% pwc
's, the tank is clean and looks clear. i changed my filter media because it was disgusting!! Oh and i added a bag of purigen to the hob
peguim. Are there any other things i am missing ? or any extra advice i should give him? he knows how to do a water change, just in case, and i brought about 10 gals of sea water just for safety in case he needs to change something.