I got one of the these modules to try and time some LEDS
What are trying to do? Do you really need true wall/calendar time or just a timing interval?
If you are trying to time between events, then things like using millis() or pulsein() are better.
Trying to use an RTC over i2c for something more precise than seconds is going to be difficult.
Depending on the accuracy needed, even if you use the sqw output, the challenge becomes syncing sqw output with the internal instance of time when the RTC bumps the second, especially since it would have to take into consideration the i2c overhead during initialization. It can be done but it isn't just a simple matter of counting sqw interrupts.
Then there is using the Alarm capability to generate an alarm every second which will assert the sqw signal, but then clearing it becomes the issue. You can save the millis() time in the ISR which can be used to sync up the RTC seconds with but if you try to clear the alarm in the ISR interrupts the Wire code will hang. But even if it doesn't hang, the i2c bus is so slow, that you would miss millis() timer ticks. So you would have to coordinate this with the foreground loop code.