Hello, I purchased a home in 2021 and thought I'd do some maintenance on the water heater (anode change, drain). I looked at the manufacturer (AO Smith) and noted the serial number indicated it was made in 2002 (it is now 2023). The water heater from the outside appears new and it works perfectly (does gurgle every now and then). So, I drained it and these "crystals" came out maybe a 1/4 cup but that was it. So moving on to the anode rod. It is NOT on the top of the water heater. There is a hot water, cold water, and TP valve and a hole for insulation. The insulation hole IS NOT the anode hole. Removed the TP valve not under there. Removed the hot water nipple, not there, either. In between the hot and cold inlets there is the word "anode" embossed on the top cover of the water heater. I removed the vent and TP valve and four screws that hold the top of cover on but can not get the top off. Tried to pry it off and it is on there. Is the anode rod under that cover? If it is since the HWH is so old (but runs great) should I just save myself the trouble and wait for it to fail?