I had the reverse happen to me last month... I was doing my morning tank check before work and I saw skunk cleaner molt pinned to the intake on my Koralia. I thought, "oh cool, Fred molted again, right on schedule!" Fred had been molting about every 3 weeks.
But then I noticed it WAS Fred. And Fred was ded. No more Fred no more.
So now, Fred's replacement, 'Bob (short for kabob) has to be found every morning or I stress a bit until I can see him...