What is the amperage on the unit’s power supply? The higher the amperage produced in the ionic foot bath the stronger the polarity field charge created in the water and the more negative ions produced giving it more pull. Most footbaths are around 1-2 amps and if more salt is put in the water than recommended, it will produce more than those amps and blow the fuse in the power supply because the power supply is cheap and can’t handle that kind of power. The more effective machines reach around 5 amps and there is even one brand that seems to be the most effective that can hover around 15amps or go even higher with a custom power supply.
Does the power supply unit say “low ripple” or say nothing at all? Ripple has to do with how much AC (alternating current) is flowing from the power supply back into the array and bath riding along the DC (direct current). AC current has a natural pulse rate of 60 hertz and can be an unhealthy frequency electromagnetic pollution for the body. Most footbaths have a low or even high AC ripple because the manufacturer must expend higher costs to make sure their power supply is made to reduce or stop any AC ripple. Most power supplies if they do not say “Low Ripple” are usually just that. I know of only a few models of footbaths that modify this power supply standard so that there is NO Ripple. Why is this important? Because besides being a harmful 60hz frequency for the body, it halts or majorly slows the effects of electrolysis of the array into the water which can majorly effect the therapeutic effect of the foot bath. Even as little as 2 volts of ripple can have a negative effect. If the array is made of stainless steel, is the 316L certified (no chromium oxide in it)? Most cheaper machines that use stainless steel have chromium oxide in it that when it ends up in the water can be incredibly toxic to the body. Only 316L does not contain chromium.
Does the ionic foot bath have a digital display? While this may seem convenient and modern, the manufacturer will have to convert some of the DC current into AC to run the display. This reduces the efficiency of the footbath which requires DC to run the array and will also cause a trickle of that converted AC to flow back or “ripple”.
What is the cost of ownership? Every bath on the market has a metal array that wears out every you turn the unit on. Ask:
How is the array constructed? Wire arrays wear out quickly and should be avoided. Check to see how complicated it is to replace the array. Some take 45 minutes and are tedious and some 5 minutes. Many of the sphere or block arrays are very frustrating to reassemble.
How long does the array last? The array should last at least 30 sessions. Most of those disposable Chinese cheese grater looking arrays do not last as long as advertised. Some arrays last 100 sessions because they are made out of a superior grade of metal.
What is the warranty? Most have a 2 year warranty. Usually the brands that charge way to much in the first place and inflate their prices. Mostly the non FDA certified brands. Most warranty claims are not covered anyway because its not a "manufacturers defect or defect in workmanship". Such as misuse and abuse of the ionic foot spa or not caring for it properly.Also using a power supply that didn't come with it too.