Uggggghhhhhhh! I knew I had a leak. The damn contractor actually started yelling...yelling.....at me that evaporation was the culprit and that all us "damn hand holding clients" think evaporation means leaks. I wasn't about to pay him the final installment until I new for sure. I used some string and measured every three hours and marked the depth. It was dropping at nearly the same rate at night and during the day. He tells me I am being "anal" and that I had to give him "his" money since the job was done and it stopped being "my" money. I calculate the surface area and tell him that I lost 400 gallons in 40 hours. He STILL says its evaporation. Then I discover that they left the float on....and the little toilet style system has been steadily flowing water in. That meant my leak was ridiculously worse than I even thought. Once he learns this he doesn't even have stones to apologize he just says "fine I'll send a guy out and when we fixes whatever tiny leak there "might" be we will fix it. But you better drain it so they can work on Monday". Ya I had to drain it. I just wanted em gone so I complied. As I come out of my house the next morning...the first thing they did was fill it. I wanted to scream but didn't. They bust out some of the rocks on the side wall and LOW AND BEHOLD....a massive leak was pouring down behind the liner under the concrete and filling a nice 100gallon or so pocket that drained in to the earth under my new patio slab and pond. The ground was sloppy wet. They patch it up. Rebuild the side wall and PRESTO...I have barely lost a few centimeters of water in 18 hours. Literally I could not possibly imagine a bigger ^@$!head then this contractor. He was fully and completely ready to shove a leaky pond down my throat then pay the one day's wages and 100 bucks in supplies to fix a leak on a 14,000 dollar job. If you live in Arizona, avoid Dynamic Landscapes at all cost.

The wet wood can be acting like a "wick" getting wet underneath and assisting in evaporation. As well much wood is full of toxic stuff - if water accumulates under neath drops can fall back into the aquarium and harm your fish. If you haven't the glass yet (dr foster and smith, ebay and other online places - petmountain so on - I've sound even ones for 75 supper cheap! and if timing is right free shiping sometimes.) Mean while you can use plastic mesh or even plastic but leave area where air can exchange or poke holes. As others have mentioned check for leaks - use tissue or anything easily absorb able to put near glass corners, bottom edges, back and see if it collects water. Get a tub ready, lol.

To save some headache this would be a good time to have an overall check of the system done with cleaning of the coils and checking the charge. I would get some quotes and consider your time and discomfort just to clean the coil.

We think that the leak has been found. They injected the dye into the light conduits and the light under the spa spillover sucked it right up. They ran another bucket test last night after they temporarily sealed the leak and my husband said it does not appear to have lost any more water overnight. They were sending one of their service guys out today to permanently seal all the light conduits. Hopefully, that will take care of everything. I guess it is the best of both worlds because it was an easy fix and if we were losing 1" of water a day to evaporation we would have been in big trouble. I don't mind running my hose a little bit but we are on well so I fear burning it up if I run it too much.