Hi everybody. My pool deck is sinking around my spa. I am looking to get it repaired but I want to make sure all of the issues are addressed. My pool builder told me that they only do complete renovations. I contacted a mudjacking company but I want to make sure that there isn't a problem with the pool and plumbing. The water level in the pool does not seem to be dropping any faster than usual but when the pump is running, the water level in the spa drops pretty quickly. There does not appear to be a check valve on the plumbing to the spa but it used to hold water when the pump is off. It seems like the water is going back into the pool but I can't be sure that it is not leaking into the ground. I do not know if the pool deck is due to a grading issue, settlement over a long period of time, or an active leak. What would usually keep the water in the pool when the pump is running when there is no check valve? Is mudjacking a good solution? Any help would be greatly appreciated.