Constant Activity on TR-004

[gemini23]

Hi. I just setup a new TR-004 DAS. I am using RAID5 Software based. Updated to latest firmware. Basically the lights and drive activity is constant. Almost like a clock. Literally everyone 1-2 seconds the 4 green lights blink and you can hear the drives as if they are being accessed. I checked every where in the software and there is no sleep mode. I'm worried that this activity is going to degrade my drives. I am using Seagate Exos Enterprise 18Tb HDDs. Any ideas? Thanks!