If you had enough calcium in your water, the MM has bound to that and should clear in a few days. In theory, the mfg suggests it will take some iron with it, because the excess calcium binds with the iron.
In my case, the mm does not cloud, because having vinyl, I have a very low calcium level to begin with.
What was your Calcium level to begin with?
Be sure to run the filter continuously for 48 hrs or more after treatment. Re: back flush...I have a sand filter and usually only have to backwash once after a treatment at 25% above clean pressure, but I don't get the cloudiness, meaning I'm not over-saturated on calcium, I suspect.
So I can't reliably estimate how often you might have to back flush, but I would hope its not crazy

The bright side is that this process should also reduce excess calcium as well.
Post back and let me know your starting Calcium level and how long it takes to clear. That would help me know whether or not I should suggest this method for other people with DE filters and higher Calcium levels.
For me, its been way easier than AA PLUS sequestrant, that will still cloud anyway, because you don't have long periods of low chlorine, the fight to get back up, or the risk of going green then shocking and starting the whole cycle over again.
And I would expect at maintenance doses you would not likely as as long a clody period or as much...but again suspect that depends on the calcium.
I hope this works out for you even if you're having temporary déjà vue
