I did my first cook , but had a terrible time keeping the coals stocked and burning . I was refilling the coals every 30 minutes . Mind you , it is a small chamber ( a handful of coals fills it ) .Do I take the grate out and pile up the lump ? or is the grate needed ? There was no burn outs , the coals just burned fast no matter how I adjusted the slide vent . Am I doing something wrong ?