I’ve used ALD twice in the past 10 months; both times were due to the same sort of issue, and both were isolated to the cause within an hour. These guys do a hreat job of telling you what is leaking and what is not. After the temporary fix done as part of the first visit got damaged by a continued progression of the degeration around the skimmer, I’ve decided to accept ALD’s offer of a guaranteed repair job. Not cheap, but at the rate it has been leaking, this work will pay for itself in about 24 months, just in savings on our water bill.