Why are all of my hard drives running so slow?

Question

Model Name:
iMac
  Model Identifier:
iMac6,1
  Processor Name:
Intel Core 2 Duo
  Processor Speed:
2.16 GHz
  Number of Processors:
1
  Total Number of Cores:
2
  L2 Cache:
4 MB
  Memory:
3 GB
  Bus Speed:
667 MHz
  Boot ROM Version:
IM61.0093.B07
  SMC Version (system):
1.10f2
  Serial Number (system):
W863768FVGN
  Hardware UUID:
00000000-0000-1000-8000-0016CB9C92A8
My hard drives run at 55 mbs according to Blackmagic Disk Speed Test.  It takes about 14 hours to back up 325 gbs.  I feel like they should be running faster.  The 2 External hard disks (one a brand new WD 2TB My Book and the other a 3 year old 1 TB Li cie) are connected directly to Mac using firewire 400 and 800 respectively.  Yes, my iMac has one 400 and one 880 firewire port.  Damned if I know which is which since they both indicate the same speed.  I use Onyx, Mackeeper, Disk Warrior and Disk Utility to keep my Mac in good order.  All Disks are healthy according to this software.  No disk has more than 33% capacity use. Is this all I should expect?  Or should I be getting better performance?  Nothing else funky is happening.  Everything else is working fine without bugs.
What else could it be?

Answer 1

Get rid of MacKeeper. There are many threads on this form about that piece of junk. Look in "More Like This" or search MacKeeper