Swimcap advice

Hi all, 

I am trying to protect my scalpwhile swimming. I purchased Aquadefense gook but am having trouble finding a satisfactory swim cap. 

I purchased what i think is a normal sized cap made by Swans, and then a larger cap that covers ears.

I feel the first cap is slightly too small and doesn't stay put well, while the other comes up over my eyebrows if i pull it tight. 

Anyone have any recommendations?