Hi Agilent community, I am seeking help with a problem I am having with the HPLC in my lab. The instrument is not used very frequently, but I have been preparing buffers every 2 weeks and storing the lines in glass bottles. I am noticing some type of visual contamination by the end of the two weeks. The buffers I use are 20 mM sodium acetate trihydrate (pH5) and 20 mM sodium acetate trihydrate + 1 M sodium chloride (pH5). I am thinking of storing the lines in an ethanol solution going forward, instead of storing in the buffer. Can anyone tell me if this is a good idea? And if so, what concentration of ethanol should I use?