Don't overpack sweet melon, out of alot of nak that you can overpack with great results, sweet melon just doesn't work. I can't find the overpack thread we've had here, but the general consensus was that sm falls short of being good in that aspect, I pack it dense in the vortex, doesn't necessarily have to be below the spire holes, as long as it's below the rim. SM can also take heat pretty well so you might want to experiment with the amount of coals you're using, I use 3 cocos and windcover to start, then either take the windcover off and leave the 3 on or take 1 off and leave the windcover with the remaining 2, you'll just get a feel for it. Good clouds all the time, with pretty much most nak flavors.
EDIT: Wild obviously types faster than my slow ass
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