What is the best and safest way to remove the bacteria flakes from a Kohler Purist BubbleMassage Air jet tub?

It is unlikely to be the hot water heater causing the smell, it is more likely the input (the well water) having excess sulfur, bacteria and/or organic material

Because it sits in the tank longer, the smell accumulates. If it is a bacterial source, the hot water tank may be a breeding ground for anerobic bacteria. Draining and doing a disinfect with Hydrogen Peroxide (H2O2) is the easiest and safest step

http://www.waterheaterrescue.com/Troubleshooting/stinky-water-in-hot-water-heaters.html

https://www.stevejenkins.com/blog/2015/02/fix-rotten-egg-smell-in-your-water/

You have air in the line and need to purge the air out no water in heat chamber is allowing it to over heat and kick breaker.

1) If your water heater plugs into outlet, then electronic gas controls are susceptible to power surge. and reversed outlet polarity, and undervoltage at outlet, lack of ground wire continuity between ground plug and manifold tube connected to bottom of gas control valve.

2) If sediment builds up inside tank, it will cover thermostat probe and cause probe to malfunction.
Tank can have sediment flakes build-up and still drain perfectly clean water.

3) There are 2 general types of Honeywell electronic gas controls valves installed on Whirlpool heaters.
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#intellivent
The gas control for atmospheric water heater (passive vent at top of heater) is modular, and is not always removed from tank when replaced.
The other gas control for power vent models is removed completely.

4) Remove thermostat from tank to reveal 3/4" opening.
Look inside tank.
To remove sediment flakes: Tape assorted plastic pipes and tubes to shop vac hose and see if flakes can be removed. And remove drain valve.
http://waterheatertimer.org/Clean-sediment-out-of-water-heater.html

5) Check that air intake is clean using feather duster or compressed air, clean combustion parts as shown in product manual. If air intake is clogged with dust, then draft vent is slowed. This causes slowed venting of hot combustion by-product that will overheat combustion chamber.
Typically this condition will trip the FV system. BUT it might also trip the gas control thermostat.
http://waterheatertimer.org/images/Flame-trap-inspection-325.jpg
Stand 3-legged water heaters on bricks so inspection and cleaning flame arrestor screen is ez.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Heating water can peculate chemicals out of water, such as metals and organics.
Especially above 138 degrees.
Have well water tested.
Turn down thermostat temperature.
Or reasonably harmless well-water bacteria can react with anode rod, or other reaction in softener, to produce colored water, and smells.
Different water can produce different sludges, brown, red, gray, black, yellow.
The sludge can also combine with deteriorating pipe flakes to clog water flow.
Sludge can accumulate over years in low spots in pipes, or at elbows and constrictions.
Have plumber flush pipes.
Or run new pipes.
Also delime tankless yearly, and flush with white vinegar as shown in product manual, and treat bacteria with H2O2 hydrogen peroxide.
http://waterheatertimer.org/pdf/Bosch_Descaling-heat-exchanger.pdf

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Safest method:
Shut off electricity to heater.
Shut the water valve.
Drain heater to below the level of the element, open hot water valve in house to vent heater to speed draining.
If the element is on top, you don't have to empty the heater.
Remove old element, install new element.
Leave hot water valve open somewhere in the house.
Turn water on.
Once air is removed at hot water valve, turn electric on.
Shut water valve.

Gary

Check for an air switch at your local hot tub store

take the old one in so they can match it up to a new one

Are they white flakes? Sounds like you have lime deposits turning loose in the plumbing.

Was the unit purchased and installed new? Maybe the privious owner had a hard water problem.

In either case, you may have to invest in a water softener.

HTH,

Mike...

maybe the motor is not working any more, if you have curent to the motor but not thru the motor you need to get a motor

go online to kohler and they will send you out a new switch,, it isn't that hard to install, this will solve your problem and I think if you tell them it was put in not to long ago they will send it for free

Remove the GFCI WALL OUTLET and try connecting those wires together blk/blk..wht 2 wht...ground to ground and then see if tub will stay on, if not suggest put back together and call qulified whirl pool tech to find short in pump motor.

Please rate. Thank you. jj505