RE: "sweetening"water tanks
Common on laid up boats the water looses the chlorene , and gets gamey.
The only solution is to fill with a heavy chlorene concentration and then flush a few times.
Baking soda can improve the water taste and should be used for the last flush , give it an hour or two to absorb any taste.
The entire system , not just the tanks need the chlorox so run till every faucet hot and cold is chlorox stinky , and disconnect the ice maker and do its feed too.
Some will leave the chlorene in fot an hour , I prefer overnight.
When going over the system be sure to look for clear plastic tubing and DISCARD it.
The smallest git of light will get thru the clear plastic and encourages the growth of green slyme in the tanks or tubing.
On a new build our preference is for 5/8 copper tubing with FLAIR fittings.
A good refrigeration grade (not NAPA) flair tool is under $50 and will last a lifetime Imperial is a brand.
The flair fittings are more expensive than rubber hose or solder fittings , but the ability to carry a bit of tubing and repair the system in place , with no torch , no local "potable" water hose will pay for the fittings cost on the first freeze , or errant toolbox damage.