Silent Water pump wanted!

Ok, problems I see with the Eheim you listed...
1. It uses AC voltage....230 volts.
2. It has low head pressure. It is quite possible that the Eheim pump may be incapable of pumping water through your loop in sufficient amounts for cooling. This is something you should be wary of when chaining so many different items in your cooling loop.
3. It has 1/4" connections. Your Kandalf uses 3/8" connections, so you will be losing flow by constriction. It is better to use a pump with equal or larger connections to avoid this. You would also need to order connectors, as this pump does not come with them.

I would say that if you want a good pump that is quiet, and is capable of handling the loop you have, you may want to check out the Swiftech MCP-355 series or the variant from Danger Den. These are very well respected among those of us in the water cooling community. The MCP-355 has 3/8" connectors, would flawlessly connect into your system, and has plenty of head pressure to push the water through your loop.

Like phreejack I'll suggest the mcp655/Liang d5, but as it was mentioned your Kandalf lcs uses 3/8" tubing so you'd have to get some 1/2" tubing and a reducer to use the 3/8" stuff. Another great pump is the mcp350/355 aka Liang ddc series pumps, these are low profile, quite, and with a modified pump top like http://www.petrastechshop.com/peddcudeddcp.html and some 3/8" barbs you'd have a more powerful, and quieter pump for your water cooling.