Basically, everything needs food. If your tank is sitting there with just live rock and sand and no nutrients being putting into the tank, stuff is going to die. When it dies, it decays and produces a lot an excess nutrients that leads to the algae bloom. These same critters that are dieing may be the same ones that were absorbing your excess nutrients when the tank was being fed and they just release it back to the water. In other words your tank is cycling again. Without some sort of constant input of nutrients, it will just continue to cycle and go through boom and bloom cycles. When the food from this die off is consumed, stuff will start to die again and the cycle will just start over again. I'm guessing that you're probably not doing water changes and other maintenance type stuff while the tank is empty, right? This probably increases the cycling issue.

The question is, is your head spinning from my post or the shooters you did last night?