After spending about 4 hours trying to make perfect 1/3 - 2/3 volume ratio ooze (being super anal like I am, it is quite difficult to heat and cool the ooze quickly and get any sort of accurate volume measurement), I had a thought; why not just use mass instead of volume? Duh. I don't know if it is going to work yet, the Lava Lamp is heating up right now.
Simply use a scale (a cheap letter scale works fine) to measure 1/3 perc and 2/3 wax by mass. I used a plastic container on the scale and re-zeroed the scale. Then slowly add 70 grams of perc, then pour in 140 more grams of wax for a total of 210 gram of ooze (this gets you close to the 1 cup volume). You can literally do this in under 5 minutes. If you decide to purchase a digital scale, try to find one that does not shut off every 30 seconds if there is no change in mass.
If this technique works, you don't have to deal with the whole antifreeze thing (I couldn't find any antifreeze that was pure Ethylene Glycol). The only variable I can think of at the moment is the variable density of different brands of paraffin wax. I have done a little bit of research and found that "paraffin" can vary from .86 to .94 specific gravity. I am currently using Gulf Wax brand paraffin wax manufactured in GA, USA by Royal Oak Enterprises, LLC.
I also changed the way I pour the ooze into the glass to prevent any sort of splashing. I made a tight slightly tapered paper funnel and poured the ooze into that which allowed a nice slow filling into the glass.
Oops, the new ooze did not "dome" as expected but 50% of it popped out from one side and is now floating at the top, partially melted. It is still one continuous body though and it is attached to the lower ooze via a semi-frozen ooze structure.