Is it common for a gas water-heater to be 50 amped?
Heating for this home is mostly gas aside from Oven and dryer, which the dryer has the option for gas but isn't connected.
If it's gas then it's prob 0 amped and if you have gas you shouldn't have electric aux heat.
Might make sure it's wired to something. Inspectors will comment you can't have a breaker always off and if you remove one you have a whole in the panel so leaving them in place and on when connected to nothing happens.
For grounding your electric service provider may have requirements. I had to install 2 rods spacerd 8' apart and connect them with a single solid core wire.
So is this your main panel and it doesn't have a main breaker?