I did quality control on  my RNA-seq data using FastQC. In the report for Per base sequence quality, there are some base positions with the quality scores less than 20 ( see attached picture) . I am just wondering if there is any way to remove these? 

I looked at the FASTQ Quality Trimmer but am not sure if  this is the right tool to use and how to use the parameter settings?

Best regards

Thanh