Good morning! We just received our hot tub the other day. The company was supposed to come and show us how to do the chemicals and such but the electrician rescheduled so they rescheduled. However I was told I have to fill the hot tub this morning before the electrician comes. I have a Caldera Vanto. I put the hose in the filter area (under the cap) and the water started coming out one of the bottom vent. As the water was coming in, so was debris. There is not a lot, but enough that I want to get it out before continuing to fill the tub. Is this normal? How do I drain it? Thank you.