Hard Disk Monitoring

Hello! I'm about to set-up a Synology NAS for the first time, and am also prearing to shuck a WD Elements 10TB first time too.

I've seen advice here to run 4 tests on a drive before using it for a NAS:
To summarize, the following steps are the best to detect and repair hard disk problems:
1) Disk -> Short self test
2) Disk -> Extended self test
3) Disk -> Surface test -> Read test
4) Disk -> Surface test -> Reinitialize disk surface
https://www.hdsentinel.com/forum/viewtopic.php?t=10709

The Short Self Test went fine, but during the Extended Selt Test the temperature rose to 57°C, so decided to stop for now.

I'm unsure how to continue. I'm aware WD Elements doesn't have good ventilation on its own, but I didn't want to remove the case before it passed all tests. (there are no warning signs currently though).

If you have advice on if this temperature rise is normal, if it's worth ventilating it during the tests before shucking (and how please), or if I should place it in the NAS to continue the tests where there's is ventilation already, if possible.

Yes, I'm afraid it is well known that some external hard disk drives can reach very high operating temperature during use, including an intensive disk test. Such high temperatures could happen so easily during an intensive copy/move operation, antivirus scan, disk defragmentation and any similar: intensive disk use can increase the temperature with 15-20 Celsius or even more (compared to the idle temperature).

This is exactly one of the purpose of the disk test: to verify how the temperature increases, how high CAN be during normal use too.

Of course in most situations we can't remove the disk drive from the external enclosure as it would void the warranty, so it is better to try to reduce the operating temperature in all (other) possible ways.

If possible, please try to position the drive differently where there is higher airflow. Maybe position a fan near the drive which could at least move the air and reduce the temperature with some Celsius.
Some of our users confirmed very good results if they place the external hard disk on a laptop cooling pad - as it can also help the hard disk drive to remain cool.