Does it hurt to drain the water from a Pebble Tech bottom pool when tile cleaning is needed?

No it doesn't hurt, but it's not necessary. New Answer... The most importiant thing regarding draining your pool is that you make sure that it is not empty long. Here is Las Vegas, when the temperature gets over 90 degrees, I refuse to leave any pool dry for more then one day (drain at night, do the work the next morning and start filling it up immediately). With a peddle tech pool it is not quite as critical as with an older plaster pool, but still the 24 hour rule is a good one to stick with.