Damn, that's a lot of ice. Are you doing 10 gallon batches?
For full disclosure, I use my IC in a backwards manner.
My copper coil is also the HEX for my HERMS, so it has a temp probe connected to one port of it. During HERMS mashing, I have my hoses set up so that the temp probe is at the output of the coil. When it comes time to chill, I swap the hoses so that the temp probe is at the input of the coil.
Then I sit the coil into my HLT, fill the HLT with ice water, and start pumping the wort through the coil. The output of the coil goes right back into the kettle.
I keep circulating this until the temp probe shows me that I am at pitching temp, then I pull the coil out of the ice water and redirect the output of the coil into the fermenter.