That 'musty' smell usually has two underlying causes, both related. First, a lack of drainage holes in whatever the mix is stored in and no air holes/loose lid on top.
The main reason is a lack of aeration (perlite), and not enough O2 in the mix. I start with ~40% perlite and usually end up with 50%+ aeration with the addition of pine bark mulch and bio char. That dirty sock smell is caused by anerobic bacteria which flourish in a oxygen deprived environment.
Easy to fix, just dump it out and let air get to it to get it right as rain. The anaerobic bacteria will die/go dormant and the aerobic bacteria will flourish as soon as air gets to it.
BTW, rice hulls are not really good for aeration. They work fine for a few months, then decompose down to a soggy mess that is the opposite of whats needed for aeration.
K is hard to come by in organics. I use kelp meal and greensand in my mixes, but also grow comfrey (AKA land kelp), that is really rich in K, even higher than kelp meal in K. Either the Bocking 14 or 4 cultivars are prefered. I mainly use it as worm food along with coffee grounds and top dress with the resulting VC. But the kelp meal and greensand compliment each other very well on their own. I add both @1cup/cf, along with the same amount of Azomite.
Once I've done my initial mixing and it goes into whatever I'm using for storage, I don't do any further mixing or turning of the mix. With adequate drainage/air and enough aeration in the mix, I've found there is no need and it's just extra work. Won't hurt if you do, but it's your call.
Wet
