Mom is correct, generally: it's dangerous to drain pools, and tends to destroy liners. But an old heavy concrete pool is usually an exception, unless it's located in a flat swampy area.

Whether you SHOULD drain or not, is another question. Your numbers don't indicate that . . . but then you didn't include your CYA ppm.

Order a K2006 kit - which you will need anyhow -- and test your CYA level: http://pool9.net/testkits/

. . . . membership upgraded.