Melting Ice – Time Lapse

How long does it take for an ice cube to melt at room temperature? I decided to try out the time lapse feature of the Nikon Capture software and using my D90. For light I used a 100 equivalent watt fluorescent screwed into a 12 inch clamp on dish fixture. Using a 50mm 1.4f D lens I used a 3.5f stop at about 1/30 shutter speed, iso 100. I thought it would be less than an hour so I set it to take a picture every minute. It ended up being 2 hours exactly before the cube completely melted. You can also see the sponge expanding as its absorbing the water. I also noticed it started melting on the right side which is where the light was. Ambient temp was about 78F and I’m sure the light added a few degrees. Any other suggestions for time lapse fun?