hi, hon ... sorry to take so long to respond ... those are the General Hydroponics' 'Power Growers' ... larger than the regular DWC, and larger than I really need :wtf: ... hold 2 gallons apiece (if I remember right) ... I now recirculate the two of them thru an additional 5-gallon reservoir I made ... with that setup, I can now leave for 2-3 days without a catastrophe, if I needed to :jointsmile: