These things are a PITA. I have been using straight water for storage but was thinking it might be wise to add a bit of hydrogen peroxide to the mix. I'm leaning that direction. I'm figured that the recommended storage solution to be some kind of sterilized pH neutral water mix. Lucky me, my tap water comes out at 6.8 and weighs in at 6.2 - 6.4 after adding nutes. Thanks for the input.