First, I have a 20X40 vinyl liner pool.
Can I take off the main drain covers without any adverse effects?
There are 2 screws on each cover. I would like to see if there is a buildup of debis inside. My main drain does not pull enough water to keep the pump primed. I have to use at least one of the 2 skimmers with the main drain to operate. I am sure it worked properly last year.
I guess the trick would be to use a really long screwdriver.
Any thoughts?

Thanks
JD