Seagate 1.5TB to Samsung 2TB Smart failed

The HD204UI is a 4K sector HDD. If your original HDD's where 512 byte sector based (high probability they were) then the only way to properly align them is by performing a factory reset with the new drives in place.
A FACTORY RESET WILL WIPEOUT EVERYTHING ON THE DISKS INCLUDING DATA!!!

You can verify your alignment by...

Download the logs via Status > Logs > Download all Logs. Unzip. The contents of partition.log will indicate whether you have 4k sector alignment.

You're looking for something similar...


   Device Boot      Start         End      Blocks   Id  System
/dev/hdc1              32     4096031     2048000   83  Linux
Partition 1 does not end on cylinder boundary.
/dev/hdc2         4096032     4608031      256000   82  Linux swap / Solaris



As you can see, the start numbers e.g. 32, are divisible by 8 indicating that the partitions are aligned properly for 4k sectors.

What version of RAIDiator are you using?

I'm not sure if it would cause SMART errors but it's a place to start.

Also, what browser are you using to view Frontview (and the SMART errors)? I have noticed that in Internet Explorer the SMART data doesn't seem to update like it should, whereas Firefox will properly show the current data.