Ladycfii, I think I've figured this out. Please correct me if I'm mistaken.

To successfully stop time:
1. stop time
2. hit play, see TIME STOPPED on screen (so the game registers the time change)
3. return to menu, switch players
Repeat all three steps above for all accounts

Upon returning:
1. hit play, see TIME STOPPED on screen
2. return to menu, change time
3. hit play again
Repeat all three steps above for all accounts.

I think I've identified the problem most of us have had with this. The game doesn't run while we're not playing it. When we exit out of it, everything freezes exactly as we left it. We've stopped the time and made sure by peeking in and saw TIME STOPPED printed on the screen.

Then we return and bring up the game. The first thing we do is change the time, and then click Play to go into the account. Because it'd be silly to click play, then come back out to change the time, then click play again, right? WRONG! That's our mistake.

You have to understand how the game works. When we're not playing in an account, nothing happens at all. Everything freezes and stays exactly the way we left it, no matter what time setting it's currently on. It stays that way until we click Play again, and in a split-second, the game looks at the current speed setting, and calculates what happened over the period of our absence multiplied by the current time setting.

BUT we've already changed the time setting so it's no longer stopped. So when the game calculates what happened during our absence, it's using the NEW time setting that we just changed it to, instead of the 'stopped' setting we had it on overnight. So our fish have starved, gotten sick, and died.

So the key is - when returning, click Play BEFORE changing the time to make the game recognize the stopped time!

So if you stop time overnight, then open the game and change the time setting BEFORE you hit play, then the game calculates how much time has passed while you were gone on that CURRENT setting, which is no longer in stopped time.

To the programmers (suggestion) - to prevent such widespread confusion, please add a short explanation to the ingame help to say that we MUST click play before changing the time upon returning. Most people would never figure this out on their own, since they have no experience with programming whatsoever.