Starting Bubbles: 55
Recommended Potions: 3 holes in the ceiling, RB Bubble
Points needed for 1, 2, 3 Star: 80 000, 110 000, 135 000
Useful Charm: the Charm of Antidote
Special bubbles: Mystery Bubbles, Infected Bubbles, Crystal Bubbles
Level EI 18-7 is quite easy t play for 3 Stars, but I have never reached 3 Stars seeing the ceiling though. In the middle area of EI18-5 you got virus bubbles that will grow together very fast, therefor you need to start out the level by bursting your way straight up through the Crystal bubbles. If you pop the lower Mystery Bubble and either buble on it’s side before the virus have grown around it, you should be quite safe.
But you also need to cut the infections that spreads to the sides short. You will get tremendous problems with very complicated banking.
It is recommended to use the RB Bubbles to stop viruses from below, as the infection is the main obstacle at level EI 18-7.
Here is a 3 Star video for you as guidance.