I saw a portables ro/di unit on amazon 75 gpd. You can connect to hose or faucet. Is this a ok size to buy if I have a 150 gallon tank, were I should i put water for storage and use for top off. And other storage should have water mixed with salt, I ask cause I want to be ready for when I have my tank. And do you need to buy conditioners to treat water or its not necessary. Any advice or suggestions cause space under my kitchen sink is a problem.