So I did a

and came up empty.
Is there a 'best way' to store
dirty microfiber towels until you have enough to justify washing them?
I had been storing them in a bucket of water with some micro-fiber restore in it (essentially pre-soaking them for a few weeks), but the last time I did this I smelled mildew. So I'm wondering if there is a better solution.
Also, my towels aren't as soft as they used to be. I'm wondering if the lengthy pre-soak is part of the problem.
Thanks in advance for any advice.