I've been thinking/dreaming of setting up a water storage system for water changes. I've seen two different threads recently where the most likely cause of massive fish die-offs is unannounced municipal (tap) water spikes. Chlor, algaecide, pH, whatever. These terrify me. Partly because I think almost everyone assumes tap water is the same this week as it was last week, and so on, but also because some of the culprits wouldn't show up in normal testing even if we did it! So for those of you that do this, what components and maintenance do your systems have? @Thunder_o_b I saw your reference to your 90gal storage system in another post, and rather than hijack that thread, I am posting here, so I obviously would love hear from you. Who else? Do you filter (what type)? Aerate? Heat? Plumbing needs? Spill/leak protection? Startup and maintenance costs? RO/DI, or tap? What conditioners/treatments/remineralizers? Design considerations? Space? Placement? What benefits do a system like this provide, for you? And why did you set it up in the first place (what problems or issues led you to this solution)? What problems do you encounter in maintaining it? Does it keep water fresh? Do you have trouble temp matching for wc's? Any bact/fung/algae issues? Smell? Please, include pics!! Follow-up question: I'm particularly interested in going to RO/DI, but I hear that these flush up to 7x the water they provide. That seems high. Is it true? Are there ways around it? Thanks!!