The one constant is, never use anything but distilled water to reduce the H2O2 when making the injection solution. Bottled water, tap water or spring water will always contain trace minerals that will react with the H2O2 and render it basically useless. Keep in mind that H2O2 is also photochemically reactive so the holding tank for the solution as well as the bulk container (in my case a 15 gallon carboy, must be kept in a dark place. In my case, the entire injection system as well as the carboy is kept in a dark closet in the basement.
It does take some 'hands on' monitoring, not set it and forget it by no means.
Finally, the Pulsa-Feeder injection pump I use has basically been trouble free for 20 years now other than me being lax in filling the holding tank and allowing the solution to drop below the pickup tube which in turn lets the pump suck air and loose it's prime (the pump injects solution under pressure to the injection point ( which is actually a self cleaning Teflon assembly that requires no maintenance) If the pump looses it's prime, it looses it's pressurization and won't inject solution. However the Pulsa-Feeder unit has built in purge valves (manually operated) on the pump head so it's just a matter of putting it in purge and running it manually until the air pocket is visible in the injection tube (which is translucent heavy wall tubing), followed by solution, then switching the purge valve back over to injection.
Be apprised, when I purchased mine 20 years ago, they weren't cheap back then and today they are substantially more expensive but my experience tells me they are basically bulletproof and I can still get replacement parts for mine direct from them.
One thing I do not do is I do not have a water softener, never have. Water is fine here without a softener once I remove the contaminats in solution.
