I have an electric Greenworks 2000 psi pressure washer that I use about once every couple of months. It has a soap tank for the detergent. When no more soap comes out through the sprayer, I can still see a little detergent at the very bottom of the soap tank. Can I store the washer like this for a couple of months, or do I somehow need to empty the soap tank after every use? And if you have this Greenworks product, how do you remove this little bit of detergent left in the soap tank? Thanks in advance!