Film/bacteria buildup in Autopot system with Canna nutrients?

within an hour? that's from the fertilizer so i'd assume it's okay. I don't think potable water (before mixing nutes) can form a biofilm that fast even in an incubator and having some hobos spit in it. clean bucket to start? "clean enough" - talking about gardening and not a surgical procedure. any rez that holds water for more than a short period of time needs some sort of agitation/oxygenation. bubbles are less effective than a powerhead, but you probably don't need a powerhead unless you are up near 50-100gallon-sized tank. I use a 1600gph powerhead in my 55-gal rez. Keeps it oxygenated and swirling. these are also called 'wavemakers' for aquariums. Fewer watts than an air pump, quieter, better oxygenation, and better agitation for keeping it mixed. Using "bubbles" suck by comparison. so, learn to differentiate that fertilizer-caused film and anything that grows in your rez a 2-4 weeks down the line. Depending on water temps, exposure to light and how often you top-off will impact how long before the water gets nasty. Smell is probably an excellent way to differentiate.