Getting through the level without thinking too much about your goals is an alternative. On top of the (really quite low) difficulty of the bubble popping itself and the challenging hardships of level completion, Bubble Safari aims to thwart your bubble destruction aims with the use of a bubble limit.
Level List.
I was able to beat level 64 by shooting half of my bubbles onto the row of steel bubbles at the beginning, allowing the spawners to build up a large amount of bubbles in the middle. I then shot so that I freed three different connected bubbles while also knocking down the steel bubbles and the spawners. This gave me the fireballs that I used to thin out some of the rotten fruit bubbles. By this time my meter was already at three stars and when I shot down the purple bubbles surrounding the fruit, it never subtracted enough to bring my level down below three stars. I hope this helps.
Leader BoardLeading TodayPtsHelpful1.20087%2.20089%3.20084%4.200100%5.200100%6.200100%7.20091%8.20097%9.20017%11.2009%13.20014%Leading this WeekPtsHelpful1.60084%2.40083%3.400100%4.400100%5.40074%6.20094%7.200100%8.20097%9.2002%11.20018%13.20019%15.2006%18.20017%Leading this MonthPtsHelpful1.140083%2.120088%3.60066%4.60065%5.60074%6.60089%7.40082%8.400100%9.4003%11.40014%13.40019%15.40014%17.4007%20.4008%22.4009%24.40000%.