You will need to drain some water out of the pool in order to reach behind the liner. It is deceiving just how powerful water is, without draining you will not be able to get so much as your fingers much below the waterline.
So long as you dont drain too much (Leave a minimum of 12-18" of water) you should experience no problems and be able to simply fill it back up.
I hope this information is helpful.
Steve Goodale
Serendipity Pools & Artificial Rock
Swimming Pool Repair Online Resource Artificial Rock - Instructional guide and online store
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